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dukeboy 04-12-2019 07:47 PM

fl250 odyssey question
hello, bought a 1978 fl250 with no engine and in really bad shape
put a 301cc predator in it i knew i was going to have aome issues due to gearing but it is so darn slow amd i dont want ro remove govenor
here is my wuestion, has anyone replaced the giant driven pulley with a smaller 40 series driven to get the gearing a little higher?

thanks dukeboy

rocketkart 04-12-2019 08:31 PM

Torque converters work kind of like a 10 speed bike. As you see the belt in the Drive clutch go up in the clutch to the top it speeds up and forces the back of the belt to go down in the driven clutch giveing it a different gear ratio. I don’t think changing the driven clutch will help. What kind of drive clutch are you running ?

dukeboy 04-12-2019 09:34 PM

i am using a 40 series on a 301 amd of course the belt is a little too marrow for the honda driven soni thougjt if incould get a 40 series that could fit on the shaft i could reduce gearing due to smaller diamater etc

Kartorbust 04-12-2019 10:56 PM

I would try to rebuild that 2 stroke engine, rather than try to use the CVT parts with a 40 series.

itsid 04-13-2019 06:48 AM

replacing an engine that ran 8000++ rpm
with the cheapest possible engine running 3600 rpm

is not going to get you near any original speeds of course,
swapping the original salsbury driver for a series 40 driver isn't a good idea either
but NOT the cause for lack of speed at all!

You are essentially left with two options if you want to get some speed:
1) remove the governor (no way around that if you intend to keep that engine)
this would only result in 5/8 of the original speed since the engine will only reach 5000-5500 rpm unmodded

2) get the original engine fixed and mounted
and you get the full performance back .. IMHO what you should really head for.

and swap to all salsbury [original engine] or all series 40 [cheap predator] TC.. DO NOT MIX


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