Clutch slipping when expansion pipe kicks in


Oct 15, 2016
I've managed to build a Super Rat from scratch meaning I bought the bottom end and everything else individually and successfully assembled. Now after achieving 49.5 the clutch can slip nasty if i don't ease into high RPM's. Smelling like burnt breaks heh. Anyhoo the rat bottom is stock from what I know. The motor head is a 6 cc with a solid copper gasket, also 26 tooth, a small reed valve with the champion carb with a #88 jet which BTW the plug never seems to look rich. I'm running Opti 2 @ 3 oz per gal. Oh and the jug is worked with 3rd reed port, transfers cleaned, ported intake and exhaust with a windowed piston that I cut and the original piston rings from that piston. I got a reading of 190 PSI from this build. She's running soooo good that the guys who race them by my way won't run one with me, they say I ain't ready, I just wanted to see how fast mine was compared to theirs. So this is my problem, the clutch slips if I don't ease off when the pipe kicks in. If I just cruise normal she's good. Can you see anything wrong with my set up? I've already looked at your clutch instructions so I'm just wondering If I can get away with loosening or tightening the butterfly. I'm so close to getting it right I love it thanks in advance.

Update: loosened the clutch cable and went for a ride and seems to not slip but still smells like it so I'm gonna change the pads since they may be bad.


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Sep 5, 2011
All I have is the dead link listed my friend is trying to source here in the US. If anyone finds someone importing now please post here.
Feb 3, 2021
I know this is an older thread. But this is relevant to your questions and cheaper!
I am in search of a new clutch plates. one of the higher end type for use with these pads they work really well just plate and stock springs. a set of these even grips the stock plate well on my minarelli issue is the stock plates are never flat and end up wearing funky!