Lacking performance at top end

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Jackomad5
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Hi guys, I have an LML 2t with various mods. Malossi 166 kit with transfers matched. mazzi racing crank, si 24 carb, simonini exhaust, carbon reeds etc. The issue i have since installing the malossi kit is that in each gear at 3/4 throttle/revs i seem to hit a brick wall where no extra speed can be gained past this point only extra vibration even though it feels as if there is quite a bit more to give. Now i understand our 2 stroke engines and their noticeable powerbands but im unsure as to whether it could be expected that on certain setups the power might drop away to such an extreme, which sounds like what some refer to as overev? or if something simply isn't right. I decided on the malossi kit for the extra rpm's and therefore greater speeds i should achieve but so far i am yet to take advantage of this!

Since improving the performance of the scooter I have struggled to keep the heat down at high revs. Not sure if these could be linked, fuel somehow not getting through? although i dont suffer with the symptoms most describe as fuel starvation.

I have tried changing the stator/CDI and Ht lead just to rule these out as well as playing with various jetting setups.
currently at 140, be3 130

Any help would be massively appreciated,from an eager amateur
mick1
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what's your timing set at ? could be too far retarded.

What's your plug colour ? could be too rich.

Bit puzzled that you hit a brick wall in paragraph 1 but struggle with heat at high rev's in paragraph 2 ? If you've got high rev's you must be getting decent power.
How do you know you've got heat issues ? what are the symptoms or have you got a gauge fitted ?
Jackomad5
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timing is 17/18 degrees. plug shows light after plug chop seemingly regardless of jetting. the scooter revs high or certainly feels as if it is but as the rpms increase at the top i cant gain anymore acceleration. The heat issue could probably be a thread all in itself but basically yes i have a CHT gauge which i got after suffering multiple heat seizures. checked rigorously for air leaks and im 99.9% sure there is no issue there.
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Shaunbond
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130 is a big MJ for that set up.
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VMSC Committed to Scootering for 25 years
mick1
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slipping clutch ?
Jackomad5
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it would seem that way but if i go much lower than 130 mj i risk seizing! i have tried lower and the issue still persists.

clutch crossed my mind Mick but i dont get any of the other issues associated with clutch slipping. unless it is possible to have problems at high rpm only. plates are not particularly old i had it out and reinstalled it recently with no difference, plates seemed fine.
mick1
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Worn/damaged reed petals..... (getting desperate now).

I wonder if the exhaust may be issue. Blocked exhaust could retain heat and lower performance
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Shaunbond
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I've Just looked at the old kits fitting instructions and they recommend a 115MJ but if with a cut crank up jet 5-7 points, so max 122. What makes you think it'll seize?

https://www.scooterhelp.com/tuning/malo ... nstall.pdf
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VMSC Committed to Scootering for 25 years
Jackomad5
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Ive already seized it shaun! multiple times with around 125mj it seems to run ok with the rich jetting. i.e it doesnt seem to bog down. throttle response is good and it revs crisp. just this issue at high rpm
Avantone
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If it’s overheated previously and it now runs crisp with what seems like a bigger MJ than needed, it sounds like an air leak - maybe establish everything’s absolutely sealed and then see how it runs.
I find using carb cleaner to check/find leaks is super quick and efficient.
Tony

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www.lambrettagearbox.com
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