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can you rock the mid shaft left and right at all? maybe you need to add a shim inside to push the idler to the left to push the pulley away from the case.

Unfortunately there is zero lateral play. It gets worse when I fully thread in the pully set screw. I prefer to not machine MIP letters on trans case

What is the exact issue? Pics? You should be able to move the pulley away from the trans by shimming it and moving the set screw slightly away?

Here are some pics. Note, the pulley has a long setscrew that goes through the drive shaft. I am not installing the setscrew fully in these photos because it's hard to remove, and I don't want to deform the threads on the pulley. Once installed, note how close the pulley is to the transmission. There appears to be clearance, but there is not. The MIP logo is pressing against the back face of the pulley.

Inside the trans, there is one shim on each side of the drive gear. It may be possible to put both on one side and provide some clearance, but not enough - I have not tried this yet.

This transmission was originally chain drive, and the sprocket did not have a clearance problem. The belt conversion simply shows replacing the gear with the pulley in this orientation. I tried fitment on another MIP trans (used condition), and it has the same dimensions and clearance issue.

I could solve the problem by milling off the MIP logo, but want to make sure there is not something wrong with the parts or assembly.

Thanks Limestang

You have to mill the MIP logo off. NIB kits I have seen came that way.

Excellent - Thanks for confirming aip47!

Hi,

If you want to retain the writing.

Turn the shaft 90 degrees, mark with a texta through the grub screw hole of the pulley,

moving the pulley out so it just clears the writing.

Now remove the shaft from the gearbox, using a drill bit, the same size as the grub screw,

drilling only deep enough for the grub screw to be able to grab on the shaft.

Replace long grub screw with a short one.

Made some progress tonight. I carefully milled about 0.02" onthe MIP trans case, eliminating the pully friction problem. I also successfully drilled th graphite chassis for mounting the front MIp hardware. Guidance for drilling graphite produced very clean holes. I will post photos this weekend.

- Limestang

glad that all worked out. Stupid you had to mill the trans case. Could have been prevented, looks like plenty of opportunity to correct the clearance from the factory on the pulley or the shaft.

would the belt have rubbed on the bulkhead if you were able to move the pulley out 20 thou?

You're correct, more clearance on the shaft would not have caused any issues. The shortness of the front CVD's is another case where a little more length makes allot of sense. I chalk it up to the early times in RC, as well as the pace at which new products were being designed and released. The system works well, but takes some effort to get it tweaked

you know, i was just thinking maybe you could have pressed the gear on the shaft over slightly. oh well, it all works now and looks great!

Found this today. Dont know if it helps..

So was the hole in the pulley shaft a production oversight, or would the ~1mm outward spacing have caused additional strain or belt misalignment issues?