clutch drag and comp ratios

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MCH
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Posts: 143
Joined: Sun Sep 04, 2011 9:09 pm
Main scooter: street racer px
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my malossi never ceases to amaze me as one problem is solved it creates another haha

i got it dynoed this year but had a pinking problem rolling off the throttle, couldn't sort it by jetting or timing, so i changed my head for a lower comp one,

originally my build had a sip head on the malossi, and that was approx 11.5-12 ratio, anyway got a 10.5 one and now that has solved the pinking issue rolling off the throttle, however my top speed seems to have decreased, before I could get up to 80mph in 4th quite easily now i struggle to get over 70mph, which leads me to think it could be the clutch,

just rebuilt the clutch with new plates, its a 7 spring t5 clutch, i tested each plate on a glass surface to make sure they were not warped and fitted them in my clutch, i previously had clutch drag issues and found my plates had eaten slightly into the clutch basket, so i cleaned up the basket with a file and fitted new plates,

anyway took it out for a spin after fitting the new head to find like above my top speed was lower in 4th, it does have a t5 4th fitted, i can get up to about 65 -67 mph in 3rd, then when changing into 4th just doesn't want to pull, which made me think is my clutch slipping is it not engaged fully, it doesn't feel like its slipping but just thinking why is not pulling like it did before with the other head on?

on my way home i had a bit of a clunky gear change manage to go from 2nd to 4th and when i arrived home, put it into 1st pulled clutch in and the clutch was dragging again,
iv adjusted the cables but not had chance to take it out again since after adjusting the clutch cable,

just thinking is it my clutch thats causing me the aggro or has the lower comp head made 4th gear not pull or is it a combo of them both?

i will have to just manage it to get it brid and back, but just wondering what it could be
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LI150
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Posts: 630
Joined: Wed Jan 07, 2009 8:30 pm
Main scooter: Series 2 LI150
Location: East Yorkshire
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Could you put the other head back on to test if it is your clutch causing issues.
MCH
registered user
Posts: 143
Joined: Sun Sep 04, 2011 9:09 pm
Main scooter: street racer px
Contact:

sorted it,

adjusted the clutch again and now i have no clutch drag,

also top speed issue was because it needs to rev to 8000 rpm + in 3rd, so that when i change to 4th the rpm is 6000 and thats the point it can pull from
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