Mon May 30, 2022 1:06 am

Ossessionato
1979 P150X, 1983 P200E, 1988 T5, 1995 PX200E, 2011 Yamaha Fazer 600 S2
Joined: 02 Aug 2015
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Location: Veria, Greece
 
Ossessionato
1979 P150X, 1983 P200E, 1988 T5, 1995 PX200E, 2011 Yamaha Fazer 600 S2
Joined: 02 Aug 2015
Posts: 3001
Location: Veria, Greece
Mon May 30, 2022 1:06 am linkquote
PSMA wrote:
Thanks!
I don't like the BGM reserve tube, its too high.
So I drive always is reserve position.
You can always trim it (I do). Apart from the undrilled BGM one I had recently, I've never had any problems with them. The SIP ones (whatever version) tend to leak after a while that's why I don't use them anymore…
Mon May 30, 2022 2:16 am

Hooked
125 GTR 1977, 50S 1975, GTS 125 Supertech 2021
Joined: 04 Aug 2014
Posts: 194
Location: Madeira Island
 
Hooked
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Posts: 194
Location: Madeira Island
Mon May 30, 2022 2:16 am linkquote
SaFiS wrote:
You can always trim it (I do). Apart from the undrilled BGM one I had recently, I've never had any problems with them. The SIP ones (whatever version) tend to leak after a while that's why I don't use them anymore…
Thanks SaFiS
I've seen somewhere someone doing that, AFAIR the mesh was unscrewed and then the plastic tube shortened. Maybe next time I remove the tank... btw, is it true you get more fuel pressure to the carb in Reserve position? eventually overcoming some restrictions/flow in fuel line and tap?

Mon May 30, 2022 6:06 am

Lucky
76 Sprint V, 63 GL, 62 VBB, 05 Stella, 66 Smallstate, 08 Stella (for now)
Joined: 16 Jun 2011
Posts: 5990
Location: Nashville
 
Lucky
76 Sprint V, 63 GL, 62 VBB, 05 Stella, 66 Smallstate, 08 Stella (for now)
Joined: 16 Jun 2011
Posts: 5990
Location: Nashville
Mon May 30, 2022 6:06 am linkquote
PSMA wrote:
btw, is it true you get more fuel pressure to the carb in Reserve position? eventually overcoming some restrictions/flow in fuel line and tap?
Not unless the laws of physics work differently where you live.

The amount of pressure in the fuel line is determined by the head height (the height of the fuel's surface above the point of entry into the carb), not the height from the top of the intake tube to the fuel's surface.

There is a nominal friction cost for running through tubing, but that's only measurable if you have meters of tubing, not a few centimeters like in this case, and mostly reduces the effective pressure if you're at maximum flow rate.
Mon May 30, 2022 7:00 am

Hooked
125 GTR 1977, 50S 1975, GTS 125 Supertech 2021
Joined: 04 Aug 2014
Posts: 194
Location: Madeira Island
 
Hooked
125 GTR 1977, 50S 1975, GTS 125 Supertech 2021
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Posts: 194
Location: Madeira Island
Mon May 30, 2022 7:00 am linkquote
chandlerman wrote:
Not unless the laws of physics work differently where you live.
I think they are pretty similar ...

Robbie, sorry, no more hijacking your thread with stupid questions, curious to know how engine revs WOT ...
Mon May 30, 2022 8:49 am

Addicted
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Location: Los Angeles
 
Addicted
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Location: Los Angeles
Mon May 30, 2022 8:49 am linkquote
chandlerman wrote:
Not unless the laws of physics work differently where you live.

The amount of pressure in the fuel line is determined by the head height (the height of the fuel's surface above the point of entry into the carb), not the height from the top of the intake tube to the fuel's surface.

There is a nominal friction cost for running through tubing, but that's only measurable if you have meters of tubing, not a few centimeters like in this case, and mostly reduces the effective pressure if you're at maximum flow rate.
It's a thing.

Fuel in reserve flows faster. Posted about this last year somewhere. Pretty sure it has to do with pressure at the valve itself.

Gave BGM the good college try. Main issue was zero fuel to the carb when riding with a low tank on steep hills.
Sat Jun 04, 2022 12:32 am

Hooked
PX
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Posts: 298
Location: Switzerland
 
Hooked
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Sat Jun 04, 2022 12:32 am linkquote
So yesterday evening was able to replace the fuel-hose for a strengthened metal-wired reinforced type fuel-hose.
The original fuel hose was the recomended 60cm but I could reduce the length of the fuel-hose by 10cm which is quite alot.
The only draw-back is I can only remove the tank if I first undo the hose from the carb inlet first and pull the hose through that way.
But better if this will prevent the fuel starvation.

I tried to fit the polini temp-sensor for the spark-plug but it is just too thick and gets jammed up against the BGM cylinder head recess for the spark-plug.
Even after grinding the spark-plug ring sensor it simply wont fit.
If I grind anymore off the sensor it will fall a part.
So its back to the screwed in to the head temp-sensor.

Carb and carb-cover cleaned and re-torqued for more jetting and temp runs….



Sat Jun 04, 2022 5:24 am

Lucky
76 Sprint V, 63 GL, 62 VBB, 05 Stella, 66 Smallstate, 08 Stella (for now)
Joined: 16 Jun 2011
Posts: 5990
Location: Nashville
 
Lucky
76 Sprint V, 63 GL, 62 VBB, 05 Stella, 66 Smallstate, 08 Stella (for now)
Joined: 16 Jun 2011
Posts: 5990
Location: Nashville
Sat Jun 04, 2022 5:24 am linkquote
Having just suffered the pain of sucking a Venturi screw into my motor, I have to ask: how you have ensured those bolts won't come loose?
Sat Jun 04, 2022 6:12 am

Hooked
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Location: Switzerland
 
Hooked
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Sat Jun 04, 2022 6:12 am linkquote
Hi CM
Loctite….
Enough or drill and wire them?

Cheers Robbie
Sat Jun 04, 2022 7:39 am

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Sat Jun 04, 2022 7:39 am linkquote
Robbie 11 wrote:
The only draw-back is I can only remove the tank if I first undo the hose from the carb inlet first and pull the hose through that way.
But better if this will prevent the fuel starvation.

I tried to fit the polini temp-sensor for the spark-plug but it is just too thick and gets jammed up against the BGM cylinder head recess for the spark-plug.
You don't have to trim a braided hose that short. That length recommendation is for the old ones that kinked easily.

Did you try feeding the sensor from the side? There's a nice window there to slide it in, at least with the Runleader's. Not that you should bother, though. The threaded sensor is
Sat Jun 04, 2022 6:08 pm

Hooked
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Hooked
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Sat Jun 04, 2022 6:08 pm linkquote
Ray8 wrote:
You don't have to trim a braided hose that short. That length recommendation is for the old ones that kinked easily.

Did you try feeding the sensor from the side? There's a nice window there to slide it in, at least with the Runleader's. Not that you should bother, though. The threaded sensor is
Thanks Ray
Ok maybe I cut the hose to short now ;(
The Polini temp-sensor definately wont fit into the cyl-head.

A question for you…
Are you running no filter or Venturi?
If Venturi, how did you secure the screws holding the ventuti on to the carb?

Cheers Robbie
Sat Jun 04, 2022 6:24 pm

Ossessionato
2007 Stella 225
Joined: 02 Nov 2019
Posts: 2684
Location: Rochester, Minnesota
 
Ossessionato
2007 Stella 225
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Sat Jun 04, 2022 6:24 pm linkquote
Robbie 11 wrote:
Thanks Ray
Ok maybe I cut the hose to short now ;(
The Polini temp-sensor definately wont fit into the cyl-head.

A question for you…
Are you running no filter or Venturi?
If Venturi, how did you secure the screws holding the ventuti on to the carb?

Cheers Robbie
I used a medium strength thread locker, and put a rag in intake anytime I had cover off to work on it.
Sun Jun 05, 2022 5:12 am

Lucky
76 Sprint V, 63 GL, 62 VBB, 05 Stella, 66 Smallstate, 08 Stella (for now)
Joined: 16 Jun 2011
Posts: 5990
Location: Nashville
 
Lucky
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Joined: 16 Jun 2011
Posts: 5990
Location: Nashville
Sun Jun 05, 2022 5:12 am linkquote
I got away with just making sure the venturi's screw were well-tightened for about four years, but the last time, I apparently failed to get it tight enough. SaFis uses threadlocker and safety wire. I'll go safety wire when I put it back on a motor. I like the ability to visually confirm the safeguard is there and working, but you have to drill the screws for the wire, which can be a bit tricky without a drill press.
Sun Jun 05, 2022 5:28 am

Jet Eye Master
PX221 MHR, O tuned PX200, PX172 Quattrini and some motorbikes
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Jet Eye Master
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Sun Jun 05, 2022 5:28 am linkquote
chandlerman wrote:
I got away with just making sure the venturi's screw were well-tightened for about four years, but the last time, I apparently failed to get it tight enough. SaFis uses threadlocker and safety wire. I'll go safety wire when I put it back on a motor. I like the ability to visually confirm the safeguard is there and working, but you have to drill the screws for the wire, which can be a bit tricky without a drill press.
8 years holding on loctite on mine. With my luck the safety wire would vibrate through and get sucked in.
Sun Jun 05, 2022 9:18 am

Hooked
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Hooked
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Sun Jun 05, 2022 9:18 am linkquote
Thanks guys very much for your tips and tricks

Cheers Robbie
Mon Jun 06, 2022 3:48 am

Hooked
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Hooked
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Mon Jun 06, 2022 3:48 am linkquote
So I could get some WOT runs in today.
Seems like the too long fuel line was an issue and now I have around a 10 degree celsius cooler temp at WOT.
Was doing 110km at around 160 celsius temp (screw-in temp sensor).

The jetting now seems worse than before.
Although it will rev-out in all gears, if Im slowly opening the throttle there will be a small sputter around 1/4 to 1/2 throttle.
At 3/4 to full throttle no splutter at all.

Since replacing the fuel line Ive restarted re-jetting again.

I was at a 130 MJ but that was definately too rich so am now on 128 MJ.
120 AC
BE4
55/160
No filter Venturi

If I rev the engine when hot at idle in neutral I have no hesitancy or splutter like when Im riding the bike.

Any suggestions to get rid of the low to mid range hesitency?

Cheers..
Mon Jun 06, 2022 7:46 am

Jet Eye Master
PX221 MHR, O tuned PX200, PX172 Quattrini and some motorbikes
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Jet Eye Master
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Mon Jun 06, 2022 7:46 am linkquote
Do a sound recording of the ride. Be sure to include WOT in 2nd gear and accelerating through the splutter point (lean splutter is very often confused with rich splutter).
Mon Jun 06, 2022 10:31 am

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Mon Jun 06, 2022 10:31 am linkquote
Jack221 wrote:
Do a sound recording of the ride. Be sure to include WOT in 2nd gear and accelerating through the splutter point (lean splutter is very often confused with rich splutter).
Hi Jack,
Thanks will do.

But now Im a little confused….
Im running the richest mixer, air-corrector and went slowly down with the main-jet from 130 to 128.

You mean the main-jet could be possibly to lean at 130?
At 130 it was spluttering in the mid range….

Cheers
Mon Jun 06, 2022 12:27 pm

Hooked
125 GTR 1977, 50S 1975, GTS 125 Supertech 2021
Joined: 04 Aug 2014
Posts: 194
Location: Madeira Island
 
Hooked
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Mon Jun 06, 2022 12:27 pm linkquote
Robbie 11 wrote:
The jetting now seems worse than before.
Although it will rev-out in all gears, if Im slowly opening the throttle there will be a small sputter around 1/4 to 1/2 throttle.
At 3/4 to full throttle no splutter at all.
Maybe the BE4? Afaik, BE4 is more greasy at low/middle revs and leaner at high revs, as opposed to BE2. BE3 would be the best compromise, any special reason for BE4?

Ps: Just using this post and the one bellow as a reference:
https://modernvespa.com/forum/post1830769#1830769

Last edited by PSMA on Tue Jun 07, 2022 2:55 am; edited 2 times in total
Mon Jun 06, 2022 2:19 pm

Jet Eye Master
PX221 MHR, O tuned PX200, PX172 Quattrini and some motorbikes
Joined: 14 Jun 2017
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Location: London UK
 
Jet Eye Master
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Joined: 14 Jun 2017
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Location: London UK
Mon Jun 06, 2022 2:19 pm linkquote
Robbie 11 wrote:
Hi Jack,
Thanks will do.

But now Im a little confused….
Im running the richest mixer, air-corrector and went slowly down with the main-jet from 130 to 128.

You mean the main-jet could be possibly to lean at 130?
At 130 it was spluttering in the mid range….

Cheers
We need to hear it. 2 strokes make specific noises when they are happy. The lean point maybe 1/4 to 1/2 throttle. This is where the pilot and main stacks hand over. I could be rich. Will know when we hear it.
Mon Jun 20, 2022 1:27 am

Hooked
125 GTR 1977, 50S 1975, GTS 125 Supertech 2021
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Posts: 194
Location: Madeira Island
 
Hooked
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Posts: 194
Location: Madeira Island
Mon Jun 20, 2022 1:27 am linkquote
Robbie 11 wrote:
Hi Jack, Thanks will do. But now Im a little confused…. Im running the richest mixer, air-corrector and went slowly down with the main-jet from 130 to 128. You mean the main-jet could be possibly to lean at 130?
At 130 it was spluttering in the mid range….
Robbie, I think you ended with the 128 main jet, right? just out of curiosity, as you are in Switzerland, what's the altitude of the place you ride? I ride at sea level btw

I ordered a main jet set from BGM, will reduce my actual 140 for a 138. It has been running great for +700 miles but maybe a tad too rich - a couple of days ago it bogged for 200 meters, my guess the spark was "half" isolated as I managed to keep it running, it got back to life after that and ride back home for around 10 miles perfectly fine again, WOT, coasting ...

Will clean the spark plug and then evaluate its behavior then with the 138 for a while.
If it rides fine maybe then do a plug chop with a new plug?
Mon Jun 20, 2022 2:14 am

Hooked
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Mon Jun 20, 2022 2:14 am linkquote
PSMA wrote:
Robbie, I think you ended with the 128 main jet, right? just out of curiosity, as you are in Switzerland, what's the altitude of the place you ride? I ride at sea level btw

I ordered a main jet set from BGM, will reduce my actual 140 for a 138. It has been running great for +700 miles but maybe a tad too rich - a couple of days ago it bogged for 200 meters, my guess the spark was "half" isolated as I managed to keep it running, it got back to life after that and ride back home for around 10 miles perfectly fine again, WOT, coasting ...

Will clean the spark plug and then evaluate its behavior then with the 138 for a while.
If it rides fine maybe then do a plug chop with a new plug?
Hi PSMA
Yes 128 mj was the last MJ size.
Im at around 450 metres above sea level.

I havent done any more work on the jetting.
Ive lost motivation and Im dissapointed with the results so far….
I thought I had a grasp on the jetting process, worked through the recomendations from others, but the more I dive deeper into the getting the jetting right, the less it seems I know.
Afraid of seezing it so will let it sit in the garage until I get the motivation back to move on…
Cheers…
Mon Jun 20, 2022 5:22 am

Hooked
125 GTR 1977, 50S 1975, GTS 125 Supertech 2021
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Posts: 194
Location: Madeira Island
 
Hooked
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Mon Jun 20, 2022 5:22 am linkquote
Robbie 11 wrote:
Hi PSMA
Yes 128 mj was the last MJ size.
Im at around 450 metres above sea level.

I havent done any more work on the jetting.
Ive lost motivation and Im dissapointed with the results so far….
I thought I had a grasp on the jetting process, worked through the recomendations from others, but the more I dive deeper into the getting the jetting right, the less it seems I know.
Afraid of seezing it so will let it sit in the garage until I get the motivation back to move on…
Cheers…
Sorry to ear that , I understand it can by frustrating ...
Your setup is somewhat similar to mine, so why not restarting with a 160/BE3 and maybe a 130? AFAIR you had a 120 air corrector, isn't that too low? you need plenty of air to that engine, drilled air filter? Sorry I can't help you more and if I contributed to introduce noise ... you just need to put that beauty running, give it a rest but not too much ...
Mon Jun 20, 2022 5:33 am

Lucky
76 Sprint V, 63 GL, 62 VBB, 05 Stella, 66 Smallstate, 08 Stella (for now)
Joined: 16 Jun 2011
Posts: 5990
Location: Nashville
 
Lucky
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Joined: 16 Jun 2011
Posts: 5990
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Mon Jun 20, 2022 5:33 am linkquote
Robbie, by way of comparison, in my VBB I'm running a long stroke cut crank with the BGM on a SprintV motor. The current jetting with no filter (bellows-to-frame) on a 24/24 is 120AC-BE4-128MJ.

I tried a 140 AC and couldn't get the mid-range rich enough. I need to check what my idle is, but it might need to be a bit richer, too.

It sounds like you're getting close. You're already miles ahead of most people when it comes to understanding jetting. You're now into the "trough of disillusionment" where you know enough to realize how much more there is still to know. I've been tuning these beasts for over ten years now and still learn new things every day.
Mon Jun 20, 2022 10:38 am

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Mon Jun 20, 2022 10:38 am linkquote
chandlerman wrote:
Robbie, by way of comparison, in my VBB I'm running a long stroke cut crank with the BGM on a SprintV motor. The current jetting with no filter (bellows-to-frame) on a 24/24 is 120AC-BE4-128MJ.

I tried a 140 AC and couldn't get the mid-range rich enough. I need to check what my idle is, but it might need to be a bit richer, too.

It sounds like you're getting close. You're already miles ahead of most people when it comes to understanding jetting. You're now into the "trough of disillusionment" where you know enough to realize how much more there is still to know. I've been tuning these beasts for over ten years now and still learn new things every day.
Thanks CHMan
Sounds like you have been there done that 👍.
Your right I need to hang-on in there and be a bit more positive
As you say there are many things to learn and every engine is different.
I will plod on and see where it brings me!

Thanks s lot…

Cheers Robbie
Mon Jun 20, 2022 11:37 am

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Mon Jun 20, 2022 11:37 am linkquote
Robbie 11 wrote:
Thanks CHMan
Sounds like you have been there done that 👍.
Your right I need to hang-on in there and be a bit more positive
As you say there are many things to learn and every engine is different.
I will plod on and see where it brings me!

Thanks s lot…

Cheers Robbie
Hi Robbie,
If you haven't already, take it out with a spanner/socket/screwdriver and warm it up.

Rotate the idle mixture screw a 1/2 turn in either direction and see how it rides. Takes me a few hours, but I'll get it to where even a quarter turn in either direction feels worse. I think I'm at 2 3/4 turns out with similar jets (no venturi).

You might be able to dial out that stutter.


Made this tool to better keep track of rotations. 8mm socket end.

Mon Jun 20, 2022 1:17 pm

Lucky
76 Sprint V, 63 GL, 62 VBB, 05 Stella, 66 Smallstate, 08 Stella (for now)
Joined: 16 Jun 2011
Posts: 5990
Location: Nashville
 
Lucky
76 Sprint V, 63 GL, 62 VBB, 05 Stella, 66 Smallstate, 08 Stella (for now)
Joined: 16 Jun 2011
Posts: 5990
Location: Nashville
Mon Jun 20, 2022 1:17 pm linkquote
My jetting is *without* my venturi installed. If you're running a venturi, you'll need to go richer. If you're already on a BE4, it may be time for a 100 AC

Ray, do you have a coarse or fine thread idle screw? If you're at 2 3/4 on a coarse screw, you need a richer idle jet, don't you?
Mon Jun 20, 2022 2:38 pm

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Mon Jun 20, 2022 2:38 pm linkquote
chandlerman wrote:
My jetting is *without* my venturi installed. If you're running a venturi, you'll need to go richer. If you're already on a BE4, it may be time for a 100 AC

Ray, do you have a coarse or fine thread idle screw? If you're at 2 3/4 on a coarse screw, you need a richer idle jet, don't you?
Spaco threads.
/1.5 turns in comparison to coarse threads.

I shelved the venturi. Don't need it...yet.
Mon Jun 20, 2022 10:39 pm

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Mon Jun 20, 2022 10:39 pm linkquote
Ray8 wrote:
Spaco threads.
/1.5 turns in comparison to coarse threads.

I shelved the venturi. Don't need it...yet.
A T5 filter and a taller top (or a spacer) is one way to avoid the screws getting eaten by the crank
Mon Jun 20, 2022 11:00 pm

Jet Eye Master
PX221 MHR, O tuned PX200, PX172 Quattrini and some motorbikes
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Posts: 3287
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Mon Jun 20, 2022 11:00 pm linkquote
Robbie 11 wrote:
Hi PSMA
Yes 128 mj was the last MJ size.
Im at around 450 metres above sea level.

I havent done any more work on the jetting.
Ive lost motivation and Im dissapointed with the results so far….
I thought I had a grasp on the jetting process, worked through the recomendations from others, but the more I dive deeper into the getting the jetting right, the less it seems I know.
Afraid of seezing it so will let it sit in the garage until I get the motivation back to move on…
Cheers…
Getting the main jet right is the first step. Seems like you're nearly there.
Easiest way to set a main jet is, start from too big and won't rev out and splutters. Then progressively smaller until it barely splutters and revs out fully. One more size down from here is usually good for road use.
The altitude won't help but procedure is the same. Stick with the AC120/BE4 combo and there will be no seizing from the jetting.
Setting the pilot jet is the difficult bit.
Tue Jun 21, 2022 3:17 am

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Tue Jun 21, 2022 3:17 am linkquote
Ray8 wrote:
Hi Robbie,
If you haven't already, take it out with a spanner/socket/screwdriver and warm it up.

Rotate the idle mixture screw a 1/2 turn in either direction and see how it rides. Takes me a few hours, but I'll get it to where even a quarter turn in either direction feels worse. I think I'm at 2 3/4 turns out with similar jets (no venturi).

You might be able to dial out that stutter.
Thanks Ray
I have also a Spaco carb with the hex nut mixture screw. The one thats difficult to get to due to the starter motor being in the way.
Should this be around 1.5 out from fully in?
Cheers
Tue Jun 21, 2022 8:37 am

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Tue Jun 21, 2022 8:37 am linkquote
Robbie 11 wrote:
Thanks Ray
I have also a Spaco carb with the hex nut mixture screw. The one thats difficult to get to due to the starter motor being in the way.
Should this be around 1.5 out from fully in?
Cheers
More like 2 1/2 -3 as a starting point. Course thread 2 is equal to 3 fine thread turns.
Tue Jun 21, 2022 8:54 am

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Tue Jun 21, 2022 8:54 am linkquote
Ray8 wrote:
More like 2 1/2 -3 as a starting point. Course thread 2 is equal to 3 fine thread turns.
Thanks Ray..
Fri Jun 24, 2022 2:00 am

Hooked
125 GTR 1977, 50S 1975, GTS 125 Supertech 2021
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Fri Jun 24, 2022 2:00 am linkquote
Robbie, do you know if the Polini rev/temp gauge works fine without a battery (Vespa battery). I see it has a button battery on the back so I guess it does? I'm looking for options and yours look awesome, you mentioned it has warning leds? ... like "orange" for a temp preset?

Looking for news from your Blueeeehh ... how's that beauty?

Thanks
Fri Jun 24, 2022 2:05 am

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Fri Jun 24, 2022 2:05 am linkquote
PSMA wrote:
Robbie, do you know if the Polini rev/temp gauge works fine without a battery (Vespa battery). I see it has a button battery on the back so I guess it does? I'm looking for options and yours look awesome, you mentioned it has warning leds? ... like "orange" for a temp preset?

Looking for news from your Blueeeehh ... how's that beauty?

Thanks
Hi PSMA
The Polini gauge needs a battery.
The small battery is only for the memory of the configuration settings set and the time.

Cheers
Robbie
Fri Jun 24, 2022 2:16 am

Hooked
125 GTR 1977, 50S 1975, GTS 125 Supertech 2021
Joined: 04 Aug 2014
Posts: 194
Location: Madeira Island
 
Hooked
125 GTR 1977, 50S 1975, GTS 125 Supertech 2021
Joined: 04 Aug 2014
Posts: 194
Location: Madeira Island
Fri Jun 24, 2022 2:16 am linkquote
Robbie 11 wrote:
Hi PSMA
The Polini gauge needs a battery.
The small battery is only for the memory of the configuration settings set and the time.

Cheers
Robbie
Thanks!
Meanwhile found the instructions on Polini site (SIP doesn't have them for download)
Will search a bit more ...

Ps: Hmmm, it seems as sensor and battery or no sensor at all ...

Regards
Fri Jun 24, 2022 3:39 am

Ossessionato
2007 Stella 225
Joined: 02 Nov 2019
Posts: 2684
Location: Rochester, Minnesota
 
Ossessionato
2007 Stella 225
Joined: 02 Nov 2019
Posts: 2684
Location: Rochester, Minnesota
Fri Jun 24, 2022 3:39 am linkquote
PSMA wrote:
Thanks!
Meanwhile found the instructions on Polini site (SIP doesn't have them for download)
Will search a bit more ...

Ps: Hmmm, it seems as sensor and battery or no sensor at all ...

Regards
I prefer a Koso setup as you can replace sensor end and they sell a kit. Also has other functions as you have noted.

These devices are a low current draw you could hook up a temporarily 12 volt source.

https://www.amazon.com/TalentCell-Rechargeable-Amplifier-Multi-led-Indicator/dp/B00MHNQIR2/ref=asc_df_B00MHNQIR2/?tag=hyprod-20&linkCode=df0&hvadid=309807921328&hvpos=&hvnetw=g&hvrand=9586937001150696664&hvpone=&hvptwo=&hvqmt=&hvdev=t&hvdvcmdl=&hvlocint=&hvlocphy=9019817&hvtargid=pla-571314857036&psc=1

Trail tech does offer a setup that doesn't require a 12 volt power source. I have one on another scooter.

https://www.trailtech.net/en-us/shop/accessories/digital-gauges/tto-mini-gauge/tto-temperature/surface-tto-temperature-black-cylinder-head-sensor-14mm/
Fri Jun 24, 2022 7:49 pm

Addicted
Joined: 29 Nov 2020
Posts: 902
Location: Los Angeles
 
Addicted
Joined: 29 Nov 2020
Posts: 902
Location: Los Angeles
Fri Jun 24, 2022 7:49 pm linkquote
PSMA wrote:
Thanks!
Meanwhile found the instructions on Polini site (SIP doesn't have them for download)
Will search a bit more ...

Ps: Hmmm, it seems as sensor and battery or no sensor at all ...

Regards
Glad you asked that question!
Was about to order one.

The displays draw so little power.

The TrailTech and Runleader are powered internally. The Runleader has a replaceable battery. The Trailtech has a non-replaceable battery, that lasts around 5 years or so without a 12v connection.
Neither requires an external 12v power source.

Thinking about connecting the Runleader to my Koso sensor to see how it goes, for the hell of it. I'll let you know how it works out.
Sat Jun 25, 2022 2:06 am

Ossessionato
2007 Stella 225
Joined: 02 Nov 2019
Posts: 2684
Location: Rochester, Minnesota
 
Ossessionato
2007 Stella 225
Joined: 02 Nov 2019
Posts: 2684
Location: Rochester, Minnesota
Sat Jun 25, 2022 2:06 am linkquote
Ray8 wrote:
Glad you asked that question!
Was about to order one.

The displays draw so little power.

The TrailTech and Runleader are powered internally. The Runleader has a replaceable battery. The Trailtech has a non-replaceable battery, that lasts around 5 years or so without a 12v connection.
Neither requires an external 12v power source.

Thinking about connecting the Runleader to my Koso sensor to see how it goes, for the hell of it. I'll let you know how it works out.
Use a multimeter and measure resistance of wires for both sensors if there the same should read close to same resistance.

Good to know about runleader having a replaceable battery.
Sat Jun 25, 2022 4:34 am

Lucky
76 Sprint V, 63 GL, 62 VBB, 05 Stella, 66 Smallstate, 08 Stella (for now)
Joined: 16 Jun 2011
Posts: 5990
Location: Nashville
 
Lucky
76 Sprint V, 63 GL, 62 VBB, 05 Stella, 66 Smallstate, 08 Stella (for now)
Joined: 16 Jun 2011
Posts: 5990
Location: Nashville
Sat Jun 25, 2022 4:34 am linkquote
Ray8 wrote:
Thinking about connecting the Runleader to my Koso sensor to see how it goes, for the hell of it. I'll let you know how it works out.
The runleader and Koso both use a Thermocoupler, so other than maybe needing some sort of offset, it should work just fine, and probably won't even be enough difference to need that, as Thermocouplers are highly standardized, with NIST and ISO standards that they are all built more-or-less in line with.

Trailtech's use a ThermoResister, so they work and play with no one.

I have a Koso CHT that I really like for the large, backlight-capable display, but with a few caveats...
1) The backlight runs off the bike's 12V DC power and is very sensitive to voltage spikes. I blew mine out when I accidentally shorted my DC to the unregulated side. The CHT has worked reliably for 5? 7? I don't know quite how many years.
2) It eats CR2032 batteries like tic-tac's. I eventually solved this problem by installing a 12V->3V Stepdown converter and grafting that to a dummy coin cell so I wasn't changing batteries twice a week.
3) Its default scale is Celsius. This is not a big deal for right-thinking parts of the world, but for those of us here in the 19th century, we still think in Imperial units and need our Fahrenheit. It's more an annoyance than anything, but having it "always on" from the bike's 12V battery solved this problem, too.

I also have a Runleader on my VBB right now and it works well as a tach, but it's basically impossible for me to read the CHT while riding. I set a backlight warning on it, but it's basically useless for any meaningful temperature monitoring.
Sat Jun 25, 2022 1:45 pm

Addicted
Joined: 29 Nov 2020
Posts: 902
Location: Los Angeles
 
Addicted
Joined: 29 Nov 2020
Posts: 902
Location: Los Angeles
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