KT100 help

F1F21

Member
So I bought a joes racing Jack shaft set up from a guy and the risers don’t seem to fit the rails on my PRC stalker nor to the bottom wing mounts. Where would be the best place to but new mounting hardware that will work for my chassis?
 
So, is the old PRC Stalker an American width rail or an International width rail?

(Copied from the Comet Kart Sales site)
What is the difference between International and American Rail?
The distance center to center between the two engine rails determine which type of mount the kart needs. International Measures 3 5/8" and American Measures 3".

Also, another explanation of mount frame widths from Rieken's Racing
https://www.out2win.com/catalog/enginemount.html

It looks like the jackshaft mount from Joes could possibly fit either but, the tapped holes for the bottom clamps might only work for an International width rail.

Brian #89
 
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I think it might just be user error 🤦🏼‍♂️😂. After looking a bit more I’ve found that there are more threaded holes for the risers to go into and I should be able to make it work I think 🤞. Does anyone know what the thread and pitch are on those plates? Because I want to run a tap through them as they look to be pretty chewed up and I don’t wanna ruin them by just running the bolt in
 
Joes Racing make a real nice jack shaft assembly. If you need parts for it either buy direct from them of try Summit or Jegs. They both sell them. Joes number is 833-BUY-JOES They’re in Washington state. This jack shaft they sell looks exactly like the ones I got from Jason Gibb at Gibb Concents Racing (GCR). It’s so alike I’m sure GCR is making them. Maybe check with Jason, I think he’s a member here.
 
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So, is the old PRC Stalker an American width rail or an International width rail?

(Copied from the Comet Kart Sales site)
What is the difference between International and American Rail?
The distance center to center between the two engine rails determine which type of mount the kart needs. International Measures 3 5/8" and American Measures 3".

Also, another explanation of mount frame widths from Rieken's Racing
https://www.out2win.com/catalog/enginemount.html

It looks like the jackshaft mount from Joes could possibly fit either but, the tapped holes for the bottom clamps might only work for an International width rail.

Brian #89
I’ve finally gotten around to measuring the rails(been working 6 days a week 12 hours days! 😳) and they are for sure American pattern. So it seems I just need to get better at my puzzle building skills and figure it out lol
 
Quick question to tag onto the kt100 motor mounts, m8x25 for the mounting bolts correct? New to the kt100 world and can't find info anywhere
 
You can do more harm with a tap than you can with a bolt. A tap will go in and cut no matter what size or cross threading you do.

If you want to know the size of the holes, you can take the bolt to an ACE hardware store and match it up or you can take a ruler and measure diameter and threads per inch. There are charts on line for standard bolt sizes to confirm your measurements.

Threads on the bottom of a KT100 are 8mm X 1.25mm.

Sundog
 
Yes the Yamaha book didn't have the size either .
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