Super Jet 91 Superjet Midshaft and Coupler?

[mmprestine]

While rebuilding my 6M6 into a 61x/62T I noticed the midshaft side coupler has stress crack in it. I would like to get a new set of couplers and just need to verify that while changing the coupler I will also have to change the midshaft, correct? Is this becuase the 650/701 midshafts are different diameter/thread on the end but the overall shaft lenght and diameter are the same so I can press it into the 650 bearing carrier? The bearings in the carrier seem very smooth and near zero runout.
Matt

 

[QuickMick]

My SJ had the same problem as yours. I ended up going with the smaller Kawai style coupler from Hot Products. There are a few people on this site now making their own brand. It just depends on how much dough you want to spend.
If you just want to replace the OEM, let me know Im sure I have a set I will never use again and will give you.

Im not sure on the thread size difference on the 650/701 though. Im pretty sure they are the same threads at the coupler.

 

[mmprestine]

So when you went with the Hot Products type did you have to change the midshaft or did they screw right on? I think I have read every thread regarding the midshafts but cannot find anything other than that the 90-93 are 20mm at the threads. Not sure why I cannot find the thread diameter of the 94-2007.

 

[QuickMick]

I should of stated that my ski is a 95. It screwed right on. I did make some spacers to go between the coupler and the shaft to close up the gap between each aluminum coupler. I wanted the shaft all the way in the housing. The spacers are only about .100 so its not a big deal. I just didnt want that 1/4" gap that I see some people have on their skiies.
I did change out a 91 shaft and dont remember the threads being smaller, but that was in 09.

Do a search with my name, I know I have pics on the X of it when I changed it over.

 

[QuickMick]

 

[JetManiac]

While rebuilding my 6M6 into a 61x/62T I noticed the midshaft side coupler has stress crack in it. I would like to get a new set of couplers and just need to verify that while changing the coupler I will also have to change the midshaft, correct? Is this becuase the 650/701 midshafts are different diameter/thread on the end but the overall shaft lenght and diameter are the same so I can press it into the 650 bearing carrier? The bearings in the carrier seem very smooth and near zero runout.
Matt

Not all 650sjs have the smaller diameter coupler threads, i think it was a 91 during the year change over. You can press the larger threaded shaft with new coupler into your housing no problem.

Otherwise just replace the defective oem coupler. We have either new shafts/couplers or used SN couplers in stock if needed.

 

[QuickMick]

Not all 650sjs have the smaller diameter coupler threads, i think it was a 91 during the year change over. You can press the larger threaded shaft with new coupler into your housing no problem.

Otherwise just replace the defective oem coupler. We have either new shafts/couplers or used SN couplers in stock if needed.

Actually I got the coupler in the pic from Chris "jetmaniac".. haha

 

[mmprestine]

Thanks guys for all the info and help. I think I will just get a new shaft and coupler set from Jetmaniac then it will be done.