Hi everyone, i need some help here cause i honestly don't know what to do anymore. After having replaced:
Fuel tank (Long range SS)
Fuel tap (Fast flow)
Stator plate (BGM)
CDI (Ducati)
Regulator (Ducati)
Wiring loom (BGM)
Key switch (Casa)
Carburettor (PHBH 30)
My bike still stutters just when is about to rev higher approx around 4/5.000 rpm there's like a revs limiter in every gear i'm running in to. And starts stuttering. It's acting exactly like when it was "fully" indian with the jetex carb, the messy loom, the rusty tank and so on…
Only thing i haven't changed is the flywheel… but before to buy one i'd like to know can the flywheel cause these symptoms? What else can be? I recently added also the frame to engine earth but the problem is still there... I still don't know how fast my bike goes since at 50 mph in 4rth gear start stuttering and won't rev anymore. I had this problem from the first day and is still there.
Any help appreciated.
Still stuttering ;(
I would include your carb jetting,ignition timing settings..top end spec and pipe(age of pipe also) and you might get your answers
True, i forgot to mention:
phbh30: Av266, X13, Idle: 55, Main 125, Slide 45
ignition timing: 16-17 approx
top end: Mugello 225
Exhaust pipe: JL3 (new, bought it last year from SIP)
The bike is pretty dead in the lower range i have to pull the clutch and open the throttle a lot to catch up the power band especially when i'm at lower revs.
when she finally catches up the power band and starts pulling decently the stuttering comes and i have to shift gear (for example from 2nd to 3rd)... So im in third and again same problem: dead at lower revs, i pull the clutch, open the throttle, she catches up the power band, starts pulling and then stuttering again until im in fourth and at 50 mph, when the last stuttering comes, i have to slow down and keep it under 50 mph, around 40-45 and keep the revs low. I hope i made myself clear
phbh30: Av266, X13, Idle: 55, Main 125, Slide 45
ignition timing: 16-17 approx
top end: Mugello 225
Exhaust pipe: JL3 (new, bought it last year from SIP)
The bike is pretty dead in the lower range i have to pull the clutch and open the throttle a lot to catch up the power band especially when i'm at lower revs.
when she finally catches up the power band and starts pulling decently the stuttering comes and i have to shift gear (for example from 2nd to 3rd)... So im in third and again same problem: dead at lower revs, i pull the clutch, open the throttle, she catches up the power band, starts pulling and then stuttering again until im in fourth and at 50 mph, when the last stuttering comes, i have to slow down and keep it under 50 mph, around 40-45 and keep the revs low. I hope i made myself clear
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ArmandTanzarian
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You've probably already eliminated this but its not just running over rich is it? That'll stutter like crazy as you open it up. If you've got an airfilter, take it off and see if it helps.
Meus Lambretta est non infractus. Is est quietus.
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Andy W
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Hi
I would check your carb set up against the ones listed on the forum to see how they compare. What float valve do you have if it is too small it won't let enough fuel into th bowl each time. Another thing to check is the flow of your fuel tap, I know you say it is new but I had one that flowed slower than an original one due to bad manufacturing.
Check all connections, once it is running strobe your timing to check it is where you think it should be. I set my static timing to 17deg with a new BGM stator and when I eventually got it to start(15-20 kicks), using a strobe showed it was ticking over at about 9-10 degs, bit of a rev (2k) and it came up to about 13/14degs. reset stator and re-strobed it and now it starts first kick as it always did and ticks over at 15degs and rev it and it sits at 17degs all the way through the rev range.
Hope this helps, Andy
I would check your carb set up against the ones listed on the forum to see how they compare. What float valve do you have if it is too small it won't let enough fuel into th bowl each time. Another thing to check is the flow of your fuel tap, I know you say it is new but I had one that flowed slower than an original one due to bad manufacturing.
Check all connections, once it is running strobe your timing to check it is where you think it should be. I set my static timing to 17deg with a new BGM stator and when I eventually got it to start(15-20 kicks), using a strobe showed it was ticking over at about 9-10 degs, bit of a rev (2k) and it came up to about 13/14degs. reset stator and re-strobed it and now it starts first kick as it always did and ticks over at 15degs and rev it and it sits at 17degs all the way through the rev range.
Hope this helps, Andy
hmmm have you got a 40 slide?...thats the one that is commonly used..what clip position is your needle set at...2nd is a favourable starting place
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col68
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- Main scooter: lambretta s2 li225 ts1
- Location: Spalding,lincolnshire
- Contact:
Have you tried an x7 2nd clip from bottom the x7 is 2mm shorter on the taper than the x13 it may clean it up . Have you done a plug chop when it is stuttering is plug black or wet looking . col
thanks all for the replyes...
The float valve is the standard 200 that came with the carb, i also have a 270 but i havent tryed it yet. The timing is a bit tricky...i strobed it but i'm still not sure about it...also i dont understand why a touring cylinder like Mugello should be so much advanced...i mean a Malossi 210 for Vespa that revs much higher should be strobed at 18 degrees according to the factory specs... so why boring Mugello at 15??
I have to try to retard it more just to see if helps...
To me that sounds more like an electrical problem because when is about the carb usually the sympthoms are more like hit and miss, in this case instead they are precise like a clock, as i said it behaves like a rev limiter... The fast flow works perfectly i checked it.
I have a X7 an X2 and a X13. Now im running the X13 2nd from top, i can try: Av266-X7 2nd- slide 40 and float 270??, advance the stator and see if it helps...?? What do you think? Thanks for the suggestions!
The float valve is the standard 200 that came with the carb, i also have a 270 but i havent tryed it yet. The timing is a bit tricky...i strobed it but i'm still not sure about it...also i dont understand why a touring cylinder like Mugello should be so much advanced...i mean a Malossi 210 for Vespa that revs much higher should be strobed at 18 degrees according to the factory specs... so why boring Mugello at 15??
I have to try to retard it more just to see if helps...
To me that sounds more like an electrical problem because when is about the carb usually the sympthoms are more like hit and miss, in this case instead they are precise like a clock, as i said it behaves like a rev limiter... The fast flow works perfectly i checked it.
I have a X7 an X2 and a X13. Now im running the X13 2nd from top, i can try: Av266-X7 2nd- slide 40 and float 270??, advance the stator and see if it helps...?? What do you think? Thanks for the suggestions!
