Sun Aug 21, 2022 12:19 pm

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Sun Aug 21, 2022 12:19 pm linkquote
How many turns out is the mixture screw?
Sun Aug 21, 2022 1:23 pm

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Sun Aug 21, 2022 1:23 pm linkquote
Jack221 wrote:
How many turns out is the mixture screw?
2.5 62/160. During the Dyno, he said it was a bit rich at the bottom end. Surely it can't be lean?
Mon Aug 22, 2022 12:56 pm

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Mon Aug 22, 2022 12:56 pm linkquote
All jetting is more on the rich side then. Time for another pressure test. Might be a small air leak somewhere.
Mon Aug 22, 2022 1:04 pm

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Mon Aug 22, 2022 1:04 pm linkquote
Great. Only really does it in 4th gear after wot. I will take a look.
Sat Aug 27, 2022 7:44 am

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Sat Aug 27, 2022 7:44 am linkquote
So there are no noticeable air leaks. If I do a wot run in 4rh with the choke out, the lurching does not happen after releasing the throttle. The bike is awful to ride but the lurching does not happen. Bigger main jet needed? Dyno lambda sensor was fine throughout the run. Strange. Could it be heating up a bit too much?
Sat Aug 27, 2022 8:08 am

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Sat Aug 27, 2022 8:08 am linkquote
But you're running a 177 kit…

A 210 kit uses around a 130-135 main (in general, with a few varying factors…)

An you're not even running a big pipe.

I'm reading you saying "lurching" is different to "surging"?

Lurching as in its like the scooter does an on/off throttle action, when you actually don't do anything?
Sat Aug 27, 2022 8:14 am

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Sat Aug 27, 2022 8:14 am linkquote
108 wrote:
But you're running a 177 kit…

A 210 kit uses around a 130-135 main (in general, with a few varying factors…)

An you're not even running a big pipe.

I'm reading you saying "lurching" is different to "surging"?

Lurching as in its like the scooter does an on/off throttle action, when you actually don't do anything?
I'm not sure how to describe it. Lurching? Surging? I come off wot after a a good 10 seconds or so. It then feels like I blip the throttle once or twice. Does this a couple of times the calms down. Only does sit at high speeds.

I briefly fitted a 68/160 idle and the problem was still there. Thing is, it runs fine with the 68/160. Does not bog when revving although it does 4 stroke a bit more at low revs.

Last edited by roody76 on Sat Aug 27, 2022 9:13 am; edited 2 times in total
Sat Aug 27, 2022 8:18 am

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Sat Aug 27, 2022 8:18 am linkquote
roody76 wrote:
I bought the bike with the same kitted fitted but it seized on me. It had been built by reedspeed and put on the dyno with the jetting as: 140/BE5/105 with 52/140 idle. It has a upgraded chamber cover and hole in carb for main jet drilled to 2.5mm. It seized on me at WOT after a good 5 or 10 mins. Massive soft seize on the intake side of piston. It was well and truly melted. I have upgraded the main jet to 112 and the plug colour is a medium brown. It feels rich when pulling away as it splutters a bit put then picks up nice. I cant see how reedpseed would set it up incorrect and a main of 130 seems huge. I have fitted a sip 2 tap. Running autolube with 1% extra in tank. Squish is quite high at 1.4mm. Cant get it any lower unless I remove the base gasket. Port height is good for all ports. Timing on stator is retarded as far as it will go to the IT setting. Compression is 170 PSI cold and 155 PSI after a run and warmed up. Its a 2016 PX150E.
I had a be5 ac140 and 122 mj on a DR177 which is not much more than a big bore upgrade and road 2; that was spot on so no wonder yours seized . I'd go back and demand they repair else you will cause a stink.
Sat Aug 27, 2022 8:20 am

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Sat Aug 27, 2022 8:20 am linkquote
ferriswolf wrote:
I had a be5 ac140 and 122 mj on a DR177 which is not much more than a big bore upgrade and road 2; that was spot on so no wonder yours seized . I'd go back and demand they repair else you will cause a stink.
We are way beyond that now. The garage bought me a new top end. It runs fine now apart from this lurching/surging issue.
Sat Aug 27, 2022 9:31 am

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Sat Aug 27, 2022 9:31 am linkquote
ferriswolf wrote:
I had a be5 ac140 and 122 mj on a DR177 which is not much more than a big bore upgrade and road 2; that was spot on so no wonder yours seized.
That jetting sounds more like it…

I'd use surging to describe when it still continues to rev when you roll off the throttle…

It's a different scenario.

And you want to make sure your "4stroking" is actually either, not enough fuel and it needs an extra cycle to gather enough to burn. Or because it's too rich and it's constantly burning fuel. Both feel the similar, but of course they're totally different problems.

A lot of people diagnose it wrong.
Sat Aug 27, 2022 9:42 am

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Sat Aug 27, 2022 9:42 am linkquote
It's definitely 4 stroking due to being a bit too rich, but this is only at low revs and doesn't bother me. If I keep the throttle open when 4 stroking, the engine temp starts to fall. I will just ride it as it is. I very rarely ride it wot so not that arsed. Temps are good which makes me not worry too much.
Sat Aug 27, 2022 12:10 pm

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Sat Aug 27, 2022 12:10 pm linkquote
roody76 wrote:
It's definitely 4 stroking due to being a bit too rich, but this is only at low revs and doesn't bother me. If I keep the throttle open when 4 stroking, the engine temp starts to fall. I will just ride it as it is. I very rarely ride it wot so not that arsed. Temps are good which makes me not worry too much.
In my ltd knowledge of the dark art of jetting if your temperature starts to fall that surely implies you're too lean on low throttle? Lean equals hot hence heat seizures . I gleam my Understanding from the gurus on here and still messaging members for advice. Your pulling away sputtering sounds more like having too lean pilot, you think it's too much fuel but it ain't, it's lack of fuel hence the lurching about. Get some richer pilots experiment .


As provided my mv member

Sat Aug 27, 2022 12:37 pm

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Sat Aug 27, 2022 12:37 pm linkquote
Did you put the pinasco Venturi on yet? What is the pilot jet now? 65/160?
Reduce the main jet until the 4 stroking goes away. Then tell us what happens.
Sat Aug 27, 2022 1:16 pm

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Sat Aug 27, 2022 1:16 pm linkquote
Jack221 wrote:
Did you put the pinasco Venturi on yet? What is the pilot jet now? 65/160?
Reduce the main jet until the 4 stroking goes away. Then tell us what happens.
I am done with the venturi as it seems to fuck it all up and doesn't quite fit under the box lid. I won't be fitting that. I am running 120/BE4/138 and 62/160 @ 2.5 turns. It only 4 strokes when riding at certain partial throttle, literally just off idle. It does not splutter at all when pinning it in any gear.

Last edited by roody76 on Sat Aug 27, 2022 1:23 pm; edited 1 time in total
Sat Aug 27, 2022 1:17 pm

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Sat Aug 27, 2022 1:17 pm linkquote
ferriswolf wrote:
In my ltd knowledge of the dark art of jetting if your temperature starts to fall that surely implies you're too lean on low throttle? Lean equals hot hence heat seizures . I gleam my Understanding from the gurus on here and still messaging members for advice. Your pulling away sputtering sounds more like having too lean pilot, you think it's too much fuel but it ain't, it's lack of fuel hence the lurching about. Get some richer pilots experiment .
I don't think that my pilot is lean at all. If anything it's rich. How would being lean reduce the temp and being rich increase the temp? You have lost me there.
Sun Aug 28, 2022 3:02 am

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Sun Aug 28, 2022 3:02 am linkquote
roody76 wrote:
I am done with the venturi as it seems to fuck it all up and doesn't quite fit under the box lid. I won't be fitting that. I am running 120/BE4/138 and 62/160 @ 2.5 turns. It only 4 strokes when riding at certain partial throttle, literally just off idle. It does not splutter at all when pinning it in any gear.
Here is a picture of my vortex. Fits fine. Whats different on yours?

If the engine is not leaking the 138MJ is way too big. Should be nearer 118. Could be hiding that your pilot jet is too small. There is so much bleed over its really hard to tell.
Put in the 68/160 pilot jet. 2.5 turns. Start reducing the main jet until it feels good and the mid spluttering has gone.


Fits just fine. Ignore dirty scooter. I've never washed it.

Sun Aug 28, 2022 3:13 am

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Sun Aug 28, 2022 3:13 am linkquote
Jack221 wrote:
Here is a picture of my vortex. Fits fine. Whats different on yours?

If the engine is not leaking the 138MJ is way too big. Should be nearer 118. Could be hiding that your pilot jet is too small. There is so much bleed over its really hard to tell.
Put in the 68/160 pilot jet. 2.5 turns. Start reducing the main jet until it feels good and the mid spluttering has gone.
Good morning.

Is 118 not a bit small for my kit? There is no mid range splutter at all. It revs nice and clean with no spluttering. 138 still revs out in second at 8900 to 9100 revs. Is this not correct?

My vortex is gold in colour with vrx or vxr on it. It seems to catch the top and rear of the air box. I can feel it make contact with the lid when I put it on.

Thanks.
Sun Aug 28, 2022 3:32 am

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Sun Aug 28, 2022 3:32 am linkquote
118 main a bit small? Not really…

You might end up around 125.

I just put a 132 main into another Malossi 210 with 60mm crank, si26 carb with a JL pipe…

It's a common jetting size on a 221cc, and it's been like that for years.

So it doesn't make much sense you're on bigger jetting with smaller cc
Sun Aug 28, 2022 3:35 am

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Sun Aug 28, 2022 3:35 am linkquote
108 wrote:
118 main a bit small? Not really…

You might end up around 125.

I just put a 132 main into another Malossi 210 with 60mm crank, si26 carb with a JL pipe…

It's a common jetting size on a 221cc, and it's been like that for years.

So it doesn't make much sense you're on bigger jetting with smaller cc
I just don't want to blow it up. I don't understand how the Dyno afr graph was spot on with the current 138 main jet. 20 jet sizes down seems excessive especially when the bike revs clean all the way. Temps around 155 wot in 4th when the temp settles.
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Sun Aug 28, 2022 3:43 am linkquote
roody76 wrote:
I just don't want to blow it up. I don't understand how the Dyno afr graph was spot on with the current 138 main jet. 20 jet sizes down seems excessive especially when the bike revs clean all the way. Temps around 155 wot in 4th when the temp settles.
Er, no mate…

Plenty of stories of where dyno runs got it wrong…

Perfect dynos, runs like shit on the street. Even seizes because it was jetted perfect on the bench, then blows up because the test is literally 60secs where on the street you have riding before and after when you try WOT.

If the dyno afr graph is right, there's a problem with your engine.

I'd definitely trust my own years of riding around with the si carb.

Nailing the pwk carb jetting with the info from jack, cm 1 and 2 and the rest of the guys, just proves the methods work.
Sun Aug 28, 2022 3:49 am

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Sun Aug 28, 2022 3:49 am linkquote
108 wrote:
Er, no mate…

Plenty of stories of where dyno runs got it wrong…

Perfect dynos, runs like shit on the street. Even seizes because it was jetted perfect on the bench, then blows up because the test is literally 60secs where on the street you have riding before and after when you try WOT.

If the dyno afr graph is right, there's a problem with your engine.

I'd definitely trust my own years of riding around with the si carb.

Nailing the pwk carb jetting with the info from jack, cm 1 and 2 and the rest of the guys, just proves the methods work.
The 138 main revs out correct in second gear and splutters. How can this be wrong? I think a 118 would seize. I am no expert but the 138 works as it should. I will put the 168/60 idle and 132 main. See how that goes and report back. I have done 1000 miles since the Dyno.
Sun Aug 28, 2022 4:02 am

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Sun Aug 28, 2022 4:02 am linkquote
Vortex has VRX-R on it. Same one as this one. They fit.

Don't go straight down to 118MJ. Just Drop a jet at a time until it feels better. With AC120/BE4/138 its sure to be way too rich. Whats the plug look like after a run?
Sun Aug 28, 2022 4:05 am

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Sun Aug 28, 2022 4:05 am linkquote
Jack221 wrote:
Vortex has VRX-R on it. Same one as this one. They fit.

Don't go straight down to 118MJ. Just Drop a jet at a time until it feels better. With AC120/BE4/138 its sure to be way too rich. Whats the plug look like after a run?
Not checked the plug for a while. Last time I checked it was light brown on the insulator and black at the thread base. No grey on the tip with a burn pattern over 50 percent on the end.
Sun Aug 28, 2022 4:11 am

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Sun Aug 28, 2022 4:11 am linkquote
Plug after a ride out today.



Sun Aug 28, 2022 5:39 am

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Sun Aug 28, 2022 5:39 am linkquote
roody76 wrote:
The 138 main revs out correct in second gear and splutters. How can this be wrong?
I think you should be asking "how can this be right"? lol…

Your setup isn't anything out of the ordinary to warrant such a large jet.

Maybe a quatrinni setup might use it… that's a 244cc setup

Plug reads are 1 piece of very limited information. the way it rides is the most important to make changes
Sun Aug 28, 2022 6:06 am

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Sun Aug 28, 2022 6:06 am linkquote
I have been out for a short ride with the 68/160 and 132 main jet. The bike felt worse. Temperatures where slightly higher than with the 138 main. The lurching appeared after a small 5 seconds WOT run. I tried a 148 main and the bike ran really poor. Spluttering like mad until it got up into the revs, but then did not rev high.

So in my opinion it ran worse with a smaller main jet and even worse with a 148 main jet.

Earlier in this thread it was assumed I would need a 130-135 main jet. Why has this now dropped by quite a bit? Unl;ess the BGM main jet kit I am using is way off on sizes. On the second gear rev test with a 138 main, it revs and then splutters ar around 9000rpm which I was advised is correct. When the lurching occurs the temps are no higher than 130 and then start to drop with minimum throttle.


Thanks.
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Sun Aug 28, 2022 6:35 am linkquote
Yeah sounds like your engine isn't quite right…

But go back to your previous settings if they work for you…
Sun Aug 28, 2022 6:42 am

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Sun Aug 28, 2022 6:42 am linkquote
108 wrote:
Yeah sounds like your engine isn't quite right…

But go back to your previous settings if they work for you…
I will leave in the 68 idle and put back the 138 main. If it feels weird I will reduce the idle 65, 62 etc until it feels good again. God knows what is causing the lurching. I will just have to live with it I guess until I need to rebuild the engine again. Probably go for the BGM 177 Pro as that seems a lot less hassle to setup.
Sun Aug 28, 2022 6:44 am

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Sun Aug 28, 2022 6:44 am linkquote
Plug looks rich but not overly. Not being black is what matters at the moment. It is running cold.

The lurching on rundown is usually a lean set up or air leak. Next time out do a recording of what it does with the 132 in.

So hard to guess with the main jet. It is an RX190 but running on a box pipe. Dyno tested at 15bhp with acceptable rich AFR. What does the plug temperature get up to at WOT? Jets can be way of size +/-10 is not uncommon.
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Sun Aug 28, 2022 6:47 am linkquote
Jack221 wrote:
Plug looks rich but not overly. Not being black is what matters at the moment. It is running cold.

The lurching on rundown is usually a lean set up or air leak. Next time out do a recording of what it does with the 132 in.

So hard to guess with the main jet. It is an RX190 but running on a box pipe. Dyno tested at 15bhp with acceptable rich AFR. What does the plug temperature get up to at WOT? Jets can be way of size +/-10 is not uncommon.
So plug temp varies at WOT depending on what gear I am in. . I had it up to 165 celcious today in 4th but not wot. Wot the temp slowly dropped to about 150 to 155 on flat road. 3rd gear wot temps about 115-120.

Last edited by roody76 on Mon Aug 29, 2022 10:57 am; edited 1 time in total
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Sun Aug 28, 2022 7:04 am linkquote
Even with the 68/160 idle, I cannot get the engine to bog down for being too rich. Even with the adjustment screw at 4 or 5 turns out. I wonder if there is a blockage in my idle circuit. Also the engine should stall when the adjustment screw is all the way in with the correct idle jet. It only does this with the 55/160 fitted. Shall I fit that again?
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Sun Aug 28, 2022 8:11 am linkquote
Just fitted the 55/160 and 138 main. Runs so much better with the smaller pilot. Revs don't hang. Exhaust starts popping at around 3500 rpm but I think that's just the exhaust on the rundown. Could a too rich idle cause the lurching issues? Then again when riding wot with choke out, there is no lurching when closing the throttle. Weird.
Sun Aug 28, 2022 8:56 am

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Sun Aug 28, 2022 8:56 am linkquote
roody76 wrote:
I don't think that my pilot is lean at all. If anything it's rich. How would being lean reduce the temp and being rich increase the temp? You have lost me there.
You said this 'If I keep the throttle open when 4 stroking, the engine temp starts to fall.' I was implying that a lean pilot would increase temperature and when you open throttle it cools because you are introducing sufficient fuel being the coolant. I didn't say lean pilot reduces temperature , when you open throttle your temperature drops, it's the fuel that cools the engine. I tried a leaner pilot in my177 as thought I was rich bogging and it lurched about, when I did plug chop the core was very pale. I changed the pilot to a richer one and the engine ran better and plug returned to brown, I wasn't rich bogging at all, I was running lean on pilot . Ended up with a 120 / 50 , a 2.4 mixture and then had to also slightly richen on the mix screw to iron out the slight splitter on minimal throttle. Jetting is tricky , it still confuses me hence getting advice on here but I've learned a lot, still a way to go.
Sun Aug 28, 2022 9:01 am

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Sun Aug 28, 2022 9:01 am linkquote
ferriswolf wrote:
You said this 'If I keep the throttle open when 4 stroking, the engine temp starts to fall.' I was implying that a lean pilot would increase temperature and when you open throttle it cools because you are introducing sufficient fuel being the coolant. I didn't say lean pilot reduces temperature , when you open throttle your temperature drops, it's the fuel that cools the engine. I tried a leaner pilot in my177 as thought I was rich bogging and it lurched about, when I did plug chop the core was very pale. I changed the pilot to a richer one and the engine ran better and plug returned to brown, I wasn't rich bogging at all, I was running lean on pilot . Ended up with a 120 / 50 , a 2.4 mixture and then had to also slightly richen on the mix screw to iron out the slight splitter on minimal throttle. Jetting is tricky , it still confuses me hence getting advice on here but I've learned a lot, still a way to go.
Now I get you. Cheers.
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Location: Planet Earth
 
Addicted
Joined: 28 May 2020
Posts: 568
Location: Planet Earth
Sun Aug 28, 2022 9:09 am linkquote
roody76 wrote:
Now I get you. Cheers.
The other thing I've been told many times is that there will always be some compromise with kitting in running. Ability to drive like hooligan WOT but some splutters at low throttle etc. some days i just wish I had my standard p200 back where it chugged along about 55 cruising and topped out 62 mph , smooth as silk, standard pipe and no pissing about with jets.
Sun Aug 28, 2022 10:32 am

Molto Verboso
Joined: 29 Nov 2020
Posts: 1033
Location: Los Angeles
 
Molto Verboso
Joined: 29 Nov 2020
Posts: 1033
Location: Los Angeles
Sun Aug 28, 2022 10:32 am linkquote
roody76 wrote:
Just fitted the 55/160 and 138 main. Runs so much better with the smaller pilot. Revs don't hang. Exhaust starts popping at around 3500 rpm but I think that's just the exhaust on the rundown. Could a too rich idle cause the lurching issues? Then again when riding wot with choke out, there is no lurching when closing the throttle. Weird.
Got some more blab for you, Roody:

Take the bike out with the 55 or 60/160 at 2.75 turns out. Then turn the mixture screw 1/2 turn in either direction and see how it accelerates. You can also likely dial-out the popping on rundown. Takes a while to sort out, but you really can't set that screw on the stand.

Check the torque on the cylinder nuts.

If possible, post a video demonstrating acceleration and the lurch, with maybe countryside cottages and windy roads through green fields, etc
Sun Aug 28, 2022 1:38 pm

Hooked
2016 PX 150 (Pinasco Vespone RX 190(On the mend))
Joined: 19 May 2022
Posts: 316
Location: UK - North East
 
Hooked
2016 PX 150 (Pinasco Vespone RX 190(On the mend))
Joined: 19 May 2022
Posts: 316
Location: UK - North East
Sun Aug 28, 2022 1:38 pm linkquote
Hello. The exhaust pops a bit even with the 68/160 fitted at 2.5 turns out. I think it's just the exhaust. With the 55 or 60/160 fitted, when going down a 1/2 mile hill at 40 in 4th, there is no popping and the engine cools down so that must be a good sign. I will try again at the weekend as I am now back at work for the week.

I will upload the video at the weekend sometime. I really like riding it, perfect or not.

Thanks.
Sun Aug 28, 2022 1:46 pm

Hooked
2016 PX 150 (Pinasco Vespone RX 190(On the mend))
Joined: 19 May 2022
Posts: 316
Location: UK - North East
 
Hooked
2016 PX 150 (Pinasco Vespone RX 190(On the mend))
Joined: 19 May 2022
Posts: 316
Location: UK - North East
Sun Aug 28, 2022 1:46 pm linkquote
ferriswolf wrote:
The other thing I've been told many times is that there will always be some compromise with kitting in running. Ability to drive like hooligan WOT but some splutters at low throttle etc. some days i just wish I had my standard p200 back where it chugged along about 55 cruising and topped out 62 mph , smooth as silk, standard pipe and no pissing about with jets.
Fully agree. This messing about gets a bit tiresome but I learn new things every time I mess with it.
Mon Aug 29, 2022 12:32 am

Hooked
2016 PX 150 (Pinasco Vespone RX 190(On the mend))
Joined: 19 May 2022
Posts: 316
Location: UK - North East
 
Hooked
2016 PX 150 (Pinasco Vespone RX 190(On the mend))
Joined: 19 May 2022
Posts: 316
Location: UK - North East
Mon Aug 29, 2022 12:32 am linkquote
One thing I forgot to mention is that with the 55/160 fitted, the bike starts after 2 or 3 kicks. With the bigger idle jets fitted it takes 7 to 8 kicks to start. Is this at all relevant?
Mon Aug 29, 2022 1:05 am

Addicted
PX 200
Joined: 25 May 2016
Posts: 927

 
Addicted
PX 200
Joined: 25 May 2016
Posts: 927

Mon Aug 29, 2022 1:05 am linkquote
Honestly, a rebuilt, tuned bike should start 1st kick… doesn't matter if it's left a day, or if it's warm.

Left over a week, it's 2 kicks.

Major factors affecting starts, jetting and ignition timing.

Something that happens often is jetting towards wrong timing

Sounds like jetting is a bit all over if it takes 7 kicks on a rebuilt engine.

Last edited by 108 on Mon Aug 29, 2022 1:08 am; edited 1 time in total
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