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I have a mhr rep 70. The bike had a pm360 pipe and ran fine. I changed out for yasuni c16 now the bike picks up to about 25mph at 11krpm then power slowly but surely falls and revs decrease.
Since then ive fitted a malossi delta force clutch and a white contra spring
Lightened the rollers too which didnt make any difference
Running dellorto 21mm with 85 main jet and open air filter
Any info help would be appreciated greatly
you have waaaay too much clutch and waaay too much roller... if the bikes revving that high, drop the clutch springs back, slow and steady dropping of the revs from 20 ish up to 40ish mph is still heavy rollers, what weight are you running? did you go WAAAAY lighter? i tend to stick the stock clutch in there, its gonna pull away shit, but get it to the point your actually rolling but maintaining speed... pin it, the revs should pick up to full and almost stay there all the way up to top speed. keep dropping roller weight till this happens, add your clutch and take it up a hill, if the revs stay high but the bike slows down, up the weight a little, if the bikes revs just die to nothing while you slow down (so stays pretty constant revs vs road speed) then there a bit too heavy, hills are amazing for this as they really do just add a bit more weight to the bike/puts more strain on the transmission, so you get a good idea of how it is actually pulling. still sounds like rollers are too heavy. keep going lighter, dont confuse clutch revs with roller revs, can have 30g rollers in there and a tight clutch and it will literally rev its tits off till the cklutch bites, and the rollers get flung out. while your on the clutch slip phase the rollers weight is pretty irelevent, this is why i say use a stock clutch, you can just ignore the fact its gonna rev slow off the line and accellerate for a bit at shit revs till its moving fast enough for the rollers to engage. it all works as one, but rpm and settings really do decide what is forcing what and how hard/wuick something moves. a stiffer contra spring will act like lighter rollers, but be harder to push up to high speeds as theres more resistance against the rollers.. again, contra springs help with off throttle on throttle power delivery, hills and deceleration rpm/resistance (engine braking effectivly)
drop the rollers, pm pipes are lazy/need heavy ish rollers/are shit
chuck an 88 in there just to be sure, wont hurt once you have the transmission set up, you can chuck a new plug in and plug chop to check its not gonna hot sieze and drop it back bit by bit, a slightly rich engine is happier than a slightly lean engine, itl have less power with slightly rich jetting too so will show up transmission setup needs alot easier (especially with hills) good luck
once you have the transmission set up, you can chuck a new plug in and plug chop to check its not gonna hot sieze and drop it back bit by bit, a slightly rich engine is happier than a slightly lean engine, itl have less power with slightly rich jetting too so will show up transmission setup needs alot easier (especially with hills) good luck