What size thread is on 1st gen shifters????
 

Having a bitch of a time getting a new shift knob to fit! I tried to put an after-market shift knob on my stock SE shifter and had no success. I cannot figure out what size and pitch fits the stock shifter. They sent me a metric 10 and a 12 but neither fit. I went to the hardware store with the stock knob and I couldn't figure out what bolts fit it... even tried some standard fittings like 1/2" and 7/16" but nope.

It seems that the 12 wants to fit... goes on a turn or two then gets stuck.

Anyone have tips on what they did to get after-market shift knob products to fit?

You sure the aftermarket one is designed to use the Mazda thread?

The aftermarket one I have uses three screws that go into the the shaft.
(I made pilot holes for them first).

Well, they told me it would fit. Here's the item: ebay

A hex nut is first put on to the shifter, which serves as a stop guide. Then a threaded adapter fits over the shifter. Finally, the knob will screw on to the adapter.

I can't get started... not even with finding a hex nut to fit on the Mazda shifter!!!

the really early 4 and 5 speed trannys from the SA's are something like 10x1.5. FB's should all be 12x1.5.....if your really curious try taking one of your rx7's wheel bolts and thread it into the stock shift knob ;) plus i retapped my 79's shift knob with a 12x1.5 and it fit perfect

Well according to their guide - it DOESN'T FIT.

Says: "This part doesn't fit the vehicle you entered. "

I PM'd them before the sale and they said it would. Listings for their other models (just different colors, patterns, etc) show the 1st gens as compatible.

Just did what you said --- took a wheel lug (12 x 1.5) and it fit perfectly!

They sent me a pair of adapters that were a 12 but they wouldn't spin on.... any suggestions?

get your money back its not going to fit

The adaptors they sent were probably a different thread pitch, like 1.25. Still 12mm but wrong pitch.

Sounds like I need them to send me 1.5 pitch. I'll go to the hardware store (again) and see if I can find a hex nut with that pitch as a test. Thx!

go to a industrial supply store, buy yourself a pitch tester for 3.00$ and save yourself a headache from now on of buying nuts

or take out the shifter and take it in to fastenal

If the wheel lug fitted perfectly... just carry one into the store for shopping nuts.

Stores usually have thread testers in the hardware section you can use, too.

It is on! Specs are 12x1.5 FINE PITCH!

Pic below.... The nut on the bottom is too thick --- making it more visible than it should be -- but what the hell, it's on! I'll find a thinner one in the future. It would have cost me $4.50 from fastenal to have it shipped in.

Attachment 715707

i like those types of shifters. nicely done!

Thx... the quality is very good -- pool ball level of finish -- and the feel is great vs the stock shifter too.