Suzuki JR-50 - Finding that extra gear

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High_Side
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Suzuki JR-50 - Finding that extra gear

#1 Unread post by High_Side »

The first year that the little JR50 was is our family was not good P.R. for Suzuki. The Mikuni carb would cause lots of trouble, usually when we were 100km from home bush-camping. It was a BIG pain in the "O Ring", but I'm confident that I finally have the problem licked.

The cool thing is that while I was googling for info on Suzuki JR50 / Mikuni carbs I came across an old note in a long dead thread on a motorcross forum that peaked my interest. Apparently there is a second (lower gear) hidden in the JR gearbox that could be "unlocked" with a dremel and some spare time (this bike suffers big time out in the foothills with only having one stock gear). Pictures were no longer available, and subsequent searches failed to turn up any more clues on how to do it so off I went looking....

Taking it apart is always easy..... Here you can see the shifter arm with one side elongated to allow the bike to go in to gear (surrounding the shaft attached to the bottom part of the spring). It became obvious when I was in here that there were two notches in the bottom of the plate (behind the spring), but only one was usable in the current configuration.
Image
A littel fun with the dremel (and the destruction of a couple of attachments
later), and the plate then looked like this:
Image
A quick check to ensure that he engagement dogs work and we're good!
Image
Hey look it still goes in to the old gear too...
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After a wait for a new gasket (pretty much a must when you split this open), and a little frustration getting the kickstart set up correctly, we've got a new low gear! A quick rip up the street and my 6 y.o. has it figured out.

Hope that this helps the next guy who comes along looking for info on the mini-JR
:righton:
Cheers,

High_Side

Next up - shaving 50 thou from the head :mrgreen:

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High_Side
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Joined: Fri Nov 28, 2003 2:05 pm
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Location: Calgary AB, Can

#2 Unread post by High_Side »

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Gadjet
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#3 Unread post by Gadjet »

Nice work Bruce. No elbow or knee guards though? I'm surprised, although I know your son has a good teacher.

Owen
1983 Suzuki GS650GL (sold)
2005 Kawasaki KLR 650 (sold)
2020 KTM 200 Duke
IBA#20953
IG: @greenmanwc

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