my BLUE Bajaj fitting 60mm Crankshaft
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Tue Jan 28, 2020 7:51 am quote
Thanks for the feedback guys every little bit helps. Qascooter the gear oil looked fine no sign of gasoline. Swiss1939 I know that is some crazy piston melt you should know. Not sure if the cylinder will survive but this is why I like Nikasil cylinder.

Thinking more about why this happened I'm concluding the SIP air filter was the culprit. We've had our share of drama just getting the air filter to fit having to resort to the DRT spacer which is excellent. On Saturday when I tested the 48-100 pilot is when I discovered the broken SIP filter. Not sure if the failure of the filter introduced any particles and maybe began some damage maybe. What I believe the SIP filter caused me to do was compensate the jetting for the SIP filter. I was confused why my main jet was what seemed small but now think this was due to the air availability with the SIP filter. It must have taken some serious forces for the steel mesh to fail like that. Air needed to get IN somehow.

When I installed the Piaggio filter it felt like it revved easier. For the wrong reasons I attributed this more to the pilot jet change. Did a blow test on the filters last night which is why I'm on this theory could barely blow air through the SIP filter but air o plenty through the Piaggio filter. So based on this its my thinking the SIP filter was suffocating the carb down and I compensated the jetting. New air filter shows this on 10 mile plug. I was hoping that color was just too few miles but on reflection it was real.

When I was ordering the filter was unable to find a Piaggio filter from SIP or ScooterCenter so I ordered the SIP version. When I got it immediately did not like it did not like the steel mesh. I do not know why I did not like it just that it was not the same as the Piaggio filter I have on my GL and I'm stubborn that way. Now I know why I do not like the SIP T5 filter. If anyone has one of these filters I'd be suspicious. Anyone have a source for an authentic Piaggio T5 air filter?

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SIP T5 air filter

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Piaggio T5 air filter

bodgemaster
1963 GL, 1976 Super (x 2), 1974 Primavera (x 2), 2006 Fly 150
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Tue Jan 28, 2020 8:51 am quote
Sorry to hear. I agree with Jack. Plug should have much more color for the number of miles on it. I donít think it was your filter. With the kit, all the porting, the long crank, the pipe, the tighter squish, you should be running a main up in the mid 120s. And bump your idle jet up too. The engine needs fuel to keep it cool.
Molto Verboso
PX221 Malossi, O tuned PX200 and some motorbikes
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Location: London UK
Tue Jan 28, 2020 9:17 pm quote
I think you're onto something with this filter change. If the filter was so restrictive it tore, then you would have been jetted a long way under for a normal filter. I do think you are borderline on the T5 Piaggio filter too.

What I would do is, rip the rest of the gauze from the SIP filter and put it back on. That way you have a small vortex and no restriction. Engine is really too tuned for this type of filter. If you have to have a filter put one on the outside of the carb box.

Found a picture of the piston from my PX200. Head has no O ring so leaks like a sieve but the burn pattern is what you will get when you're jetted correctly.

PX200 DEC19.JPG

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Wed Jan 29, 2020 3:22 pm quote
Dropped some acid today, this time into the Pinasco. Seems to have worked fairly good revealing the real damage. Don't know does it look like it will work?

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Molto Verboso
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Wed Jan 29, 2020 3:51 pm quote
Andy, I'd say you're fine. Cleaned up nicely. Photos are from a friend's Rally (Malossi 221). Fuel tap went bad (no fuel flow) and he killed the piston at WOT. It's been doing great after clean up with acid and a new piston...

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Thu Jan 30, 2020 4:31 pm quote
Thanks a bunch SaFiS your friends looks like it might have come out better than mine but can see similarities in the outcome. Maybe we will get another chance with a new piston. I'm optimistic and things should go even better with improved air flow. Got something new from supershops!

Any comments on the burn pattern? Things look pretty symmetrical I'm seeing 4 circles, there are two large almost circles that encompass most of the piston from the transfer ports. There is a clean division in the middle. The one on the clutch side seems smaller. Then there is the combustion bowl circle at the top on top of the two big circles this must be from the head. Then the clean crescent at the bottom at the exhaust.

Should we stick with the current squish? Think I'm at 0.75-.080 mm we have a thicker head gasket.

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The nylon mesh on this looks very good

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Wed Feb 05, 2020 3:54 pm quote
A new piston has arrived but it's slightly different. The new piston does not have the upper port opening on the boost port. I'm not sure what that one is for is it to scavenge from the boost port on a two port engine or is it useful for 3 port engines as well?

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Molto Verboso
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Wed Feb 05, 2020 11:09 pm quote
yes, and yes..... and yes, you should cut it again but it doesn't need to be as big. Keeps the piston cooler.
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Sat Feb 08, 2020 3:28 pm quote
Take Two
A little more progress following the acid trip. Think we may have been chasing the tail of the wrong dragon but it's been a fun learning curve let's see.

Put a window in the new piston bolted and running again with 0.5 mm head gasket. Started off with 52-120 pilot 2-1/2 turns BE4-120-135 main jet. Let idle on stand for 15 minutes. Fuel leaking out rear of air box, air filter saturated. Observe excessive blow back. Drop main to 125 take for spin. 8 mile test plug looks wet and hot.

Long story short back to 55-160 pilot and 135 main jet. May have unlocked the code. Seems idle is calling for faster beat than what I was attempting to establish.

How many miles to break in piston?

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this is becoming fun

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copper spray not silicon

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BR8HS 1st look 52-120 pilot 2.5T BE4-120-125 main jet

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BR8HS 55-160 pilot 2.5T 128 main jet

Plug burn looks cleaner with smaller pilot ground strap looks weak

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40 mile plug BR8HS 55-160 pilot 2Turns 135 main jet

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air filter a little wet at carb opening otherwise clean

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air filter after 60 miles

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60 miles on NYLON air filter

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Molto Verboso
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Sun Feb 09, 2020 8:37 pm quote
Right on Hibbert - glad it's back on the road!
Addicted
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Sun Feb 09, 2020 9:48 pm quote
Piston hole looks factory - and is on the side rather then the top - so two good things. 🙂

Glad to hear your back on the road.
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Mon Feb 10, 2020 9:51 am quote
Was thinking things would be fairly simple with the new piston and air filter. Thought the idle jet was close but seems the new air filter is calling for new settings.

Initially started with the 52-120 pilot which is on the rich side and 135 main jet. This soaked the air filter in 15 minutes idling on stand. Notice some vapor at idle and a good amount of excess fuel blow out when throttle is opened. Felt taking the main down helped stand point of view. Test ride was OK.

Came back and popped in a richer 48-100 pilot. Began doing plug chops at idle. Kept removing black wet plugs. Began leaning pilot incrementally until I arrived at 55-160 and upped main to 135.

Looking at plug on regular idle speed shut down so far. This may have been a big problem. Maybe OK for idle but yesterday I did some engine cut chops and things look scary.

I did 4 test's, 2 at 40 mph one at 45 and 50(indicated). After the first test with the 55-160 pilot & 135 main I increased the pilot two points with a 50-120. Things still look weak so add 138 main jet. I am perplexed with each adjustment going rich the plug shows the opposite or so it seems. The plug color is grey almost a blue color and very uniform.

For the test I made sure I had a solid 2 mile non-stop run holding throttle to maintain speed. For the 40 and 45 mph test it's barely past 1/8 throttle in 4th. On the 50 mph test not even sure if it's in 1/4 throttle not sure it's one the main jet it's just beginning to make excellent power.

The change from 135 to 138 was noticeable in the idle speed it came down.

Without having a larger main I remembered Jack221 suggesting a WOT test in 2nd so I gave 2nd a good ring out borrowing again from Jack it felt like it had swallowed the 138.

Came home and did a regular shut down chop to compare. Oh my gosh looks like a rich mess very deceiving.

Here's the part that's confusing me, is the main jet the weakness at this throttle stage? Seems like if I richen the pilot the idle chop looks flooded and excessive blowback but 1/8 throttle position looks lean? When I increased the main to 138 the plug color became lighter?

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chop @ 40 mph 55-160 pilot 135 main jet

why does this have more color with less fuel?

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chop @ 40 mph 50-120 pilot 135 main jet

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chop @ 45 mph 50-120 pilot 135 main jet

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chop @ 50 mph 50-120 pilot 138 main jet

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chop @ idle 50-120 pilot 138 main jet

Molto Verboso
PX221 Malossi, O tuned PX200 and some motorbikes
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Mon Feb 10, 2020 11:37 pm quote
To simplify the confusion, for the first stage, job 1, ignore everything that doesn't happen at WOT and max rpm in 2nd gear. If this is not correct, all the throttle positions less than WOT will be inconsistant. Once the main jet is set (or near enough) then other throttle positions will adjust reliably.

AC120 138MJ is usually over rich but as making better power, is just more correct than 135MJ. On a 190 cylinder this should really be flooding out by 138MJ. Did you do all the carb mods?
Drill out the float bowl to 2.0mm?
Fast flow fuel tap?
Raise the float bowl 3 mm? https://www.sip-scootershop.com/en/products/spacer+float+chamber+serie_92270000

If there is a fuel delivery issue, that isn't fixed, you're going to be needing another piston before long
Hooked
'63 VBB2T - '76 Sprint V. - '86 PX200E - '18 300 GTS Super Notte
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Tue Feb 11, 2020 8:02 am quote
Man.. What a journey with the jetting.
That's something that really concerns me for my build.. I have no other clue that what a friend told me.. I have been working a lot on my motor, would not like it to blow up the piston...

Keep on posting, I'll keep on reading
Molto Verboso
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Tue Feb 11, 2020 9:53 am quote
How is your fuel pipe? The correct length? No kinks? It may be worth disconnecting it at the carb banjo and measuring how much fuel is being delivered per minute, particularly once the tank gets towards the reserve level. It should not be a problem, but worth checking.
Ossessionato
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Tue Feb 11, 2020 9:58 am quote
are you running a fuel pump? I think not, but can't remember....
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Wed Feb 12, 2020 2:33 pm quote
OK room for improvement then. Fast flow petcock and fuel line are in good working order but we haven't completed any carb mods. Ordered the 3mm spacer. Picked up a 30 piece micro drill set at harbor freight. The drills are a little short had only 2mm into the chuck. Could not find a hand device so resorted to a 3/8" Milwaukee drill motor can't believe I did it but it's done at least the bowl passage to the main jet is opened up to 2mm. When I was finished I could see the drill bit in the pocket below the main jet. Have some questions about the other passage sizes.

Borrowing again from Sime66 this time his photo's. Below are the measurements I'm finding using Sime66 legend. What should they be?

A) Float needle duct - a 3 mm drill fits until it reaches the brass
E) Needle Seat - a 2 mm drill fits loose through here 2.35mm does not fit
B) Banjo passage what needs to be done here
C) Fuel exit - Photo only shows one side. FMP's video does something strange here, he shows something for s split second then distorts the area and puts some text I cannot remember. A 2mm drill fits and stops at brass. Do both sides get something?
D) Main passage - drilled to 2mm

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I rode this today

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Before the root canal

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the Milwaukee

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light shinning through 2mm hole

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3mm drill on top stops at brass 2mm drill loose in needle seat brass 2.35mm does not fit

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fuel exit from needle 2mm drill fits stops at brass

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Molto Verboso
PX221 Malossi, O tuned PX200 and some motorbikes
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Location: London UK
Wed Feb 12, 2020 11:53 pm quote
Brave using an electric drill. Would be so easy to go through the bottom. As this wasn't drilled 2mm, I think this was the main issue. The float spacer is just insurance (I have one on mine). The float top enlargement is optional IMHO.

Does the 138MJ flood out now? this is the big question.
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Sun Feb 16, 2020 12:46 pm quote
Running again noticeably different. Seems the pilot is now getting sufficient flow as this has become rich. On the other hand still ate up the one three eight.

Blew the head gasket. Resealed into 150 main jet pilot down to 45-140. Running, not good, rich down low but can pass it and feels like again no end, almost. There are periods of richness but if I concentrate just on 2nd gear ride it right can take it all the way again no sputter but it can also break up if not giving it what it wants. Feel it load when coasting down, down shift in a turn too much gas when open throttle. Idle is faster, maybe not too fast not sure. But it's too rich from 1/8-1/4 before it moves to main jet power then it's just ON. Blow head gasket again same place. Piston looks more "washed" now on the 150.

Trying to make sense of things thinking maybe have a squish and head torque issue. Squish was 0.75-0-.80mm with a 0.50mm head gasket torqued to 168 in pounds.

Rebuild head again with 0.80mm head gasket which should increase the squish to 1.0mm lower compression and hoping this won't blow. Main jet 145. Better, bottom still rich idle seems fast but ok but gurglely from 1/8-1/4 before it passes and moves into power. If cruising at 30 mph in 4th and WOT it gurgles and farts a bit before it passes and moves into power. Same process at 40 mph no gurgle seems already past that spectrum but it's a dirty 40 mph and slow at making power.

Tried 55-160 pilot again. Idle speed great but too much gas out the gate and does not clean up. Back to 45-140

Drop main to 142. Better but still not entirely clean in the low range. Idle speed is peppy but tolerable. Engine speed drops OK. Plug chop looks better but still weak. Engine runs OK but not as good as it should. Going rich on pilot drops idle but loads low end. Larger main seems to diminish performance. When the main is reduced seeing brown beginning to appear at the tip of ground strap and insulator is beginning to take color or change from blue grey to something else? Not sure what to do next.

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50-120 Pilot BE4-120-138 main probably head leaking

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1st head leak

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1st head leak

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45-140 pilot BE4-120-150 probably head leaking

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2nd head leak

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2nd head leak

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145 main jet @ 40 mph

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145 main jet @ 50 mph

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142 main jet at a dirty 40 mph

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142 main jet normal shut down hot plug

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Molto Verboso
PX221 Malossi, O tuned PX200 and some motorbikes
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Location: London UK
Tue Feb 18, 2020 12:41 am quote
I am concerned that you can still get high rpm in 2nd with a 150MJ. This should be flooding so bad you can't ride it at high rpm. It clearly needs the raised float spacer. Hope it arrives soon.

Edit: change the BE4 to BE3. 150MJ is too big for a BE4.
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Tue Feb 18, 2020 9:33 pm quote
The 3mm float bowl spacer arrived. Seems the original screws are a tad short will need to find longer 4.5mm bolts. Might have been leaking was afraid to over tighten with only 2-3 threads into the carb.

What is the purpose of the air filter spacer?

Wow major change. Swapped to BE3 and started with 145 main jet. Idle good rev great and sputtery in all the gears. More sputtery in the high rev than ever before. Although it was mega rich it felt good again. The richness and power was consistent all the way. Did not bother with plug chop.

Down to 138 main jet. Still rich but can feel it's trying. First time it's sputtery on higher revs it's gurgling at 50. Plug chop color wise in my eyes looks weak but the engine is not behaving that way?

Down to 132 oh my gosh it's a monster. I want it to be this. It feels so good a slight rich feeling off throttle but totally awesome. Plug chop looks weak!

Up to 135 main jet dial back air fuel 1/4 now at 2 full turns. It's great not feeling sputter in high rev anymore like with 138 and the bottom is better but not perfect. There is a little richness in the bottom again. With the 132 main jet felt almost perfect with 135 needs more work on bottom. Idle calmed I like it.

This is my interpretation based on how it drives. When I do the plug chops so surprised to see the grey color.

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cutting hole of gasket for bottom of 3mm spacer

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float bowl screws a tad short

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spacer installed

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3mm air filter spacer

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air filter spacer what's it for?

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BE3-120-138 main jet

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132 main jet

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132 main jet normal shut down

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135 main jet

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135 main jet normal shut down

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Last edited by hibbert on Wed Feb 19, 2020 11:41 am; edited 2 times in total
Molto Verboso
1980 P125X, 1980 P200E , 2005 Stella 177
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Tue Feb 18, 2020 11:04 pm quote
I see you added a gasket above and below the spacer. I was wondering about this. I thought that might need to have two gaskets like that, but then thought about it more and I think you only need one below the spacer (unless the float hits the gasket with the addition of the spacer). My thinking is that you only need to seal the lower part of the float bowl cause the fuel doesn't enter where the spacer is below the lid. I could be wrong though, especially if the float hits the gasket mounted below spacer once you add the spacer.

Also regarding plug "chop" being grey. How many miles did you run and check it at? It may be fine after 60+ miles with a 135mj, takes a little while for the tip to gain color.

Edit: just to clarify.. MIGHT be good after 60+mi. I'll defer to the jetting experts cause my last run was a seize 6 mos ago!
Molto Verboso
PX221 Malossi, O tuned PX200 and some motorbikes
Joined: 14 Jun 2017
Posts: 1668
Location: London UK
Wed Feb 19, 2020 9:30 am quote
Less concerned now. Monster and gurgling at high rpm are the right words for this stage. Sticking with the AC120 BE3 135MJ all focus is now on the pilot jet. This you need to set richness at 1/4 throttle. And be as near to 2.5 turns as possible. nowhere near as easy as it sounds. Whatever you do don't drop the main jet. Plug colour will get better with the correct pilot.
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Thu Feb 20, 2020 3:50 pm quote
Thanks Swiss1939 think it needs an additional gasket for the bottom of the spacer that way it's not metal on metal. I left the upper gasket alone just cut a hole for the bottom one so the float can get past.

Could not find M4.5 bolts so drilled the bowl top and spacer so a M5 could pass then sent a M5 tap into the carb. Got 5mm longer bolts so got back the 3mm plus added 2mm more thread I'm pleased.

For the plug chops try to get 6-8 miles to warm up then do a 2 mile continuous run before shut down. Getting fairly quick now with the routine.

Dropped the pilot one to 38-120 and set the air fuel to 2.5. Seems to like it. Most of the gurgle is gone it's negotiable now. Seems to be a little more vibration now in the 50 mph + range not sure if it's an issue or if I'm just super paranoid. Think I'm feeling a little load up on compression and noticed a flooded engine after a parking will have to keep on eye on that.

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gasket sandwich

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longer M5 hex bolts

Molto Verboso
1980 P125X, 1980 P200E , 2005 Stella 177
Joined: 20 Jul 2018
Posts: 1564
Location: Staten Island, NY
Thu Feb 20, 2020 3:56 pm quote
Awesome! I'm about to do the same with my carb tonight as I finally got my spacer. Thanks for the tip as I was wondering this for a few days without everything here to test.
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Thu Feb 20, 2020 3:58 pm quote
swiss1939 wrote:
Awesome! I'm about to do the same with my carb tonight as I finally got my spacer. Thanks for the tip as I was wondering this for a few days without everything here to test.
Get a 20mm and 30mm M5 bolt then.
Molto Verboso
PX221 Malossi, O tuned PX200 and some motorbikes
Joined: 14 Jun 2017
Posts: 1668
Location: London UK
Fri Feb 21, 2020 2:33 am quote
No not paranoid. Good call. Vibration usually means too weak. I would think 38 is too weak at low throttle. 45/140 would probably make a better curve.

Nice job on the carb.
Hooked
1984 PX(177)EFL
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Posts: 221
Location: Cornwall UK
Sat Feb 22, 2020 6:40 am quote
Glad to see you getting on top of this after your seize, Hibbert, and glad that it wasn't worse Ė it's easily done, which is why I've waited until I was in the right frame of mind to tackle mine. I won't confuse your thread with my data, but I'm starting at a similar point to where you are now, which, encouragingly, isn't so different from my jetting on the similar engine I'm running now.
Molto Verboso
1980 P125X, 1980 P200E , 2005 Stella 177
Joined: 20 Jul 2018
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Location: Staten Island, NY
Sat Feb 22, 2020 8:01 am quote
Jack221 wrote:
Edit: change the BE4 to BE3. 150MJ is too big for a BE4.
Still trying to wrap my head around this atomizer concept even after a year of reading the same articles and threads discussing it.

From my understanding on the lets talk about atomizer threads, a BE3 atomizer is leaner down low and richer up high revs, whereas a BE4 is richer down low and leaner up high revs. So wouldn't switching from BE4 to BE3 make the MJ at WOT excessively rich when keeping the MJ same? Also as mentioned by Hodge in that thread, its not so linear of a concept but more acting to move the middle point of transition between idle/main stack.. so that would mean a BE3 has a lower transition point (gets off the idle jet faster), and a BE4 has a higher transition point ( stays on the idle jet longer). Would this be why you want to use a BE3 instead of BE4 with 150MJ? to get fully MJ stack quicker in the rev range and spread that rich MJ out over more volume, because its much larger than the idle, so it needs more volume/area/time to be usable, whereas if it was dumped out in a smaller volume/area/time, its too much.

What is the usable range of MJ for a BE4 atomizer, if 150 MJ is too big for it?
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Sat Feb 22, 2020 8:10 am quote
Thanks guys good to see you again sime66. Needed some peace of mind so ran a few more tests with the 138 main jet.

1st with 138MJ with BE3. Gurgle again up into the high rev and 4 stroking if lagging in gear.

Next 138MJ with BE2 since going in that direction cleaned up most of the mid range gurgle. Engine felt like it wanted to rev higher but gurgling. Thought might be onto something.

Drop back to 135MJ and BE2. A slight bubble off throttle then be ready for take off.

Increase pilot to 45-140. Rich again off throttle after passing rich spot explosion of power perhaps greater but not smooth delivery. In hindsight I might have adjusted the air fuel down to get better results?

Put the 38-120 pilot back in, this feels the better.

Seems that 138MJ is too big. Seems BE2 has cleaned up most of the mid range and 38-120 pilot feels good at 2 1/2 turns.

Going to give this a new plug a few miles and see how it goes.

FEFDC127-2200-419B-B0F7-545C2708F78F.jpeg
Bajaj Chetak with rear mount spare tire

ED3D1D94-BEE2-4D65-AB70-024FAE968C74.jpeg
Gas/oil on top hat of float bowl. Is it leaking or blow back?

F6D0E3C6-79E2-4B45-93CE-0F409CE71C20.jpeg

Molto Verboso
PX221 Malossi, O tuned PX200 and some motorbikes
Joined: 14 Jun 2017
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Location: London UK
Sun Feb 23, 2020 1:35 am quote
The BE2 is too weak for a tuned scooter. And also dosen't work reliably with an AC120. BE3 is the weakest that is reliable.

Try BE3 and a 132MJ for a while. If you had spluttering at 138 when WOT then 132 could be ok.

38/120 is still a rich pilot. 42/160 is probably the weakest to try.

So thats 2 options to stop using the BE2
Molto Verboso
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Sun Feb 23, 2020 8:19 am quote
Wow hibbert, this is pretty damn interesting, I started at the beginning and at first was quite confused as to why you were changing both main jets and pilot jet at the same time, if the pilot is big enough you should have room to adjust the screw right ? And if its making a differnce well isn't the pilot size in the correct range?
Really admiring how you're documenting for reference,
Looking at your chops the 135 is giving a nice cigarette ash color, which is what I use to look for on a 4 stroke motor , whether these are the same really and honestly I'm just trying to learn as these 2 stroke motos scare the crap out of me.
I think though once you think you have it close you may try a new set of plugs just to have a clean canvas to go on and re-test.
Following.
Molto Verboso
2018 GTS300 Super Sport - Donatello Vespace
Joined: 22 Dec 2012
Posts: 1353
Location: Toronto, Ontario Canada
Sun Feb 23, 2020 8:42 am quote
I remember the Bajaj so well, while living and working in India, in 2008. It was as ubiquitous as the Vespa is in Italy. they were used for EVERYTHING! All the auto rickshaws were powered by Bajaj

Pashminas_080403_25.jpeg

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Sun Feb 23, 2020 11:34 am quote
Lynnb wrote:
Wow hibbert, this is pretty damn interesting, I started at the beginning and at first was quite confused as to why you were changing both main jets and pilot jet at the same time, if the pilot is big enough you should have room to adjust the screw right ? And if its making a differnce well isn't the pilot size in the correct range?
Really admiring how you're documenting for reference,
Looking at your chops the 135 is giving a nice cigarette ash color, which is what I use to look for on a 4 stroke motor , whether these are the same really and honestly I'm just trying to learn as these 2 stroke motos scare the crap out of me.
I think though once you think you have it close you may try a new set of plugs just to have a clean canvas to go on and re-test.
Following.
Thanks Lynnb and I must say I'm admiring your body work, it's my worse suit.

To understand things it boils down to weak jetting that caused the seizure. But understanding what led to that is also important. I was using a metal screen SIP air filter. As it turns out it was highly restrictive opposite of what it was supposed to be. This unknowingly required the compensation of the carburetion. When the broken air filter was discovered I swapped it out for a genuine Piaggio T5 filter and unknowingly the jetting became dangerously lean and yes it ran GREAT! If you examine the failed air filter you'll notice the metal mesh began tearing points where there is a support or riser post behind the screen. This post provided some support for the screen but on the unsupported area is where the metal weakened and tore. Think about taking the untorn screen and trying to tear it with your hands no you can't do it. Then as a stupid test I tried to blow my breath through it. No you can't do that either.

My notes are helpful for me because I have a terrible memory. It also helps me record what has been tested, the results and where logic should take you. Unfortunately I need someone else to do the interpretation and provide the logic.

697A44B5-01B1-425B-916D-7AD2C48391FC.jpeg
these are the 2 major tears almost completly torn

58C5ED51-6A47-45B5-AD0B-1271DBCB039F.jpeg
opposite side 2 more that may become one complete tear

B8C10F94-61AA-4324-A612-7D950ECEC7B4.jpeg
the post behind the screen



Last edited by hibbert on Sun Feb 23, 2020 4:51 pm; edited 1 time in total
Molto Verboso
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Joined: 07 Nov 2012
Posts: 1376

Sun Feb 23, 2020 2:17 pm quote
Wow that filter self destructed, so I wonder if you ran it with the filter without the sides if it would richen up?

Thanks for the compliment on the body work , its coming slowly , basicly just finished off the frame and scuffed up all the other parts or most of them , still need to take the front fender of and fix a ding but I may come back to it. Going to hang everything from the ceiling , give a wipe down with rubbing alcohol , one more epoxy on the metal thats bare and prime.
Hooked
2007 Stella 150
Joined: 02 Nov 2019
Posts: 218
Location: Rochester, Minnesota
Sun Feb 23, 2020 4:10 pm quote
Lynnb wrote:
Wow that filter self destructed, so I wonder if you ran it with the filter without the sides if it would richen up?

Thanks for the compliment on the body work , its coming slowly , basicly just finished off the frame and scuffed up all the other parts or most of them , still need to take the front fender of and fix a ding but I may come back to it. Going to hang everything from the ceiling , give a wipe down with rubbing alcohol , one more epoxy on the metal thats bare and prime.
It should lean out as there is more air and less fuel. That things looks like it was so restrictive, that it was like running with a choke on. When the T5 filter was installed it removed the restriction, let more air in but he didn't increase the jet size, so the air to fuel ratio leaned out as there was more air in the ratio with the same amount of fuel.

I've seen people remove the mesh and replace it with foam to allow more air. That is my plan but I need to get some foam first.
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Sun Feb 23, 2020 4:43 pm quote
Just when I think I know something I don't and Jack politely points me in the right direction. This is my usual life experience nothing unusual.

After settling on the 135MJ and BE2 I was to take a 50 mile round trip with the boys to celebrate a 53rd birthday. Rain canceled the ride but on the short drive to the shop I realized the set up was not great. It began feeling that I needed to use more throttle than it should. Got a ride in a car for the party and for the scooter drive home later I was with another scooter and drove much slower than I had been. Noticed some issues and was running potential jetting recipe's through my mind. Went to bed.

Before the attempt at the 50 mile run I had read up on the let's talk atomiser thread and read about setting the air fuel screw. I used the technique and raised the idle speed then closed the air fuel screw and backed it out in 1/4 turn increments. Found the sweet spot where the idle increased and from that point beyond not doing much. When it was dynamically set it was at 2 turns.

Great news and new jetting profile to test this morning, thank you Jack! This was the setting (BE3 132MJ 38-120 pilot) I really like before that I labeled Monster. However today's test was at 2 turns on the air fuel before I tested at 2 1/4. Two turns is better. This might be it.

Took a 50 mile round trip just 2 photo op stops. Went to Long Beach hit the traffic circle (Roundabout) at Pacific Coast Highway circled and came back home. Scooter ran awesome took it up to 60 mph and still scared to go faster. After looking at the plug when I got home don't think I'll be as fearful tomorrow.

Float Bowl Spacer - After installing the spacer noticed flooded engine when parked. First when doing plug chops trouble starting. Then getting fuel same problem. Then getting much needed grocery, beer, same thing. Light bulb came on. Excess fuel in bowl at shut down. Have to change my behavior on this, need to shut fuel OFF and run down bowl before shutting engine OFF. Seems to be working.

54DA065A-8CDF-4376-874B-E52C1A7121DA.jpeg

AB53FF7C-B43E-4C17-BAA6-1D38070C05D4.jpeg

775E4202-95DE-468D-8DA1-C65F50007285.jpeg
50 miles BR8HS shut down HOT plug 120AC BE3 132MJ 38-120 pilot 2 turns

Molto Verboso
08 GTS 250, 79 P200E, 62 Allstate
Joined: 11 Jan 2006
Posts: 1418
Location: Florence, OR
Sun Feb 23, 2020 5:23 pm quote
Right on Hibbert! That mural is cool, and painted on my birthday

Thanks for the pics and the detailed blow-by-blow in your tuning adventure!
Hooked
2007 Stella 150
Joined: 02 Nov 2019
Posts: 218
Location: Rochester, Minnesota
Sun Feb 23, 2020 7:11 pm quote
hibbert wrote:
Just when I think I know something I don't and Jack politely points me in the right direction. This is my usual life experience nothing unusual.

After settling on the 135MJ and BE2 I was to take a 50 mile round trip with the boys to celebrate a 53rd birthday. Rain canceled the ride but on the short drive to the shop I realized the set up was not great. It began feeling that I needed to use more throttle than it should. Got a ride in a car for the party and for the scooter drive home later I was with another scooter and drove much slower than I had been. Noticed some issues and was running potential jetting recipe's through my mind. Went to bed.

Before the attempt at the 50 mile run I had read up on the let's talk atomiser thread and read about setting the air fuel screw. I used the technique and raised the idle speed then closed the air fuel screw and backed it out in 1/4 turn increments. Found the sweet spot where the idle increased and from that point beyond not doing much. When it was dynamically set it was at 2 turns.

Great news and new jetting profile to test this morning, thank you Jack! This was the setting (BE3 132MJ 38-120 pilot) I really like before that I labeled Monster. However today's test was at 2 turns on the air fuel before I tested at 2 1/4. Two turns is better. This might be it.

Took a 50 mile round trip just 2 photo op stops. Went to Long Beach hit the traffic circle (Roundabout) at Pacific Coast Highway circled and came back home. Scooter ran awesome took it up to 60 mph and still scared to go faster. After looking at the plug when I got home don't think I'll be as fearful tomorrow.

Float Bowl Spacer - After installing the spacer noticed flooded engine when parked. First when doing plug chops trouble starting. Then getting fuel same problem. Then getting much needed grocery, beer, same thing. Light bulb came on. Excess fuel in bowl at shut down. Have to change my behavior on this, need to shut fuel OFF and run down bowl before shutting engine OFF. Seems to be working.
The flooding sounds like your needle and seat aren't working. Does the spacer just raise the entire assembly so you get more fuel in the bowl?
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Joined: 19 Jun 2007
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Sun Feb 23, 2020 8:23 pm quote
Christopher_55934 wrote:
hibbert wrote:
Just when I think I know something I don't and Jack politely points me in the right direction. This is my usual life experience nothing unusual.

After settling on the 135MJ and BE2 I was to take a 50 mile round trip with the boys to celebrate a 53rd birthday. Rain canceled the ride but on the short drive to the shop I realized the set up was not great. It began feeling that I needed to use more throttle than it should. Got a ride in a car for the party and for the scooter drive home later I was with another scooter and drove much slower than I had been. Noticed some issues and was running potential jetting recipe's through my mind. Went to bed.

Before the attempt at the 50 mile run I had read up on the let's talk atomiser thread and read about setting the air fuel screw. I used the technique and raised the idle speed then closed the air fuel screw and backed it out in 1/4 turn increments. Found the sweet spot where the idle increased and from that point beyond not doing much. When it was dynamically set it was at 2 turns.

Great news and new jetting profile to test this morning, thank you Jack! This was the setting (BE3 132MJ 38-120 pilot) I really like before that I labeled Monster. However today's test was at 2 turns on the air fuel before I tested at 2 1/4. Two turns is better. This might be it.

Took a 50 mile round trip just 2 photo op stops. Went to Long Beach hit the traffic circle (Roundabout) at Pacific Coast Highway circled and came back home. Scooter ran awesome took it up to 60 mph and still scared to go faster. After looking at the plug when I got home don't think I'll be as fearful tomorrow.

Float Bowl Spacer - After installing the spacer noticed flooded engine when parked. First when doing plug chops trouble starting. Then getting fuel same problem. Then getting much needed grocery, beer, same thing. Light bulb came on. Excess fuel in bowl at shut down. Have to change my behavior on this, need to shut fuel OFF and run down bowl before shutting engine OFF. Seems to be working.
The flooding sounds like your needle and seat aren't working. Does the spacer just raise the entire assembly so you get more fuel in the bowl?
Yes it raises the float and level 3mm. Guessing the fuel is equalizing out the Venturi because Iíve seen it do it with my own eyes. Just didnít understand fully until the light bulb came On.
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