So, I need to put a shift knob on my e28. I have the stock one somewhere, but I'm not very confident in it. I think I want to fab up my own shift knob.
Since it is a BMW, it uses a compression fit to secure the knob. No threads, no detent, just friction.
Here is a BMW shifter for reference. (Not my exact model!)
This is for a drift car, so I want something that is solid.
My current idea is to find some pipe that fits snug on the shifter, then drill through bot the pipe and the shifter so I can put a bolt through to secure it, and then I can weld whatever I want to on the pipe for a knob.
Open to input from anyone else on other ideas or tweaks to this idea. Like I said, I just want it to be simple and solid. And quick. My event is in 2 weeks, so I'm not trying to go crazy with this.
You could find a die to thread the top of the shifter, then tap and thread on whatever you want. Makes height adjustment easy, which might be important in your intended application.
You don't have to drill all the way through the lever, just enough indentation that a set screw gets a good grip on it. Make your knob from wood or acetal plastic and tall enough that when you use it your hand is above the set screw. I would make the screw enter from the front left, about 11 o clock when viewed from above. If wood I would use a thread insert. I have made them from aluminum, but do not recommend it for thermal reasons, both cold and hot.
I have had a press on knob depart the lever on an autocross course, not pretty....
If things don’t work out, I’ve got the stock shift knob from my e36 m3 that you could have for the price of shipping!
O2 pilot's idea is also a very good one.
What do you mean by confidence? Are you concerned it will slip off the lever? It could be glued on, or use something like strips cut from a soda can to make shims to tighten up the fit.
stuart in mn said:
What do you mean by confidence? Are you concerned it will slip off the lever? It could be glued on, or use something like strips cut from a soda can to make shims to tighten up the fit.
Correct. But I don't want to glue it on in case I need to take it off later. The soda can shims is a pretty good idea for the stock knob.
A friend took a pool ball, drilled slightly smaller than the shift lever, got it really hot, and banged it on. Very secure, but probably will have to be broken to remove.
I sent a home brewed shift BMW shift extension out in my GRM secret Santa box this year - it was just a length of aluminum with a hole just slightly larger than the stock shifter and a couple set screws in it. The other end had a grip for a mountain bike on it for comfort. I used it in my E30 for a while and it worked very well. I'll see if I can find a picture.
Azryael
New Reader
5/3/19 2:06 p.m.
We've made knobs out of delrin and wood, giving it shape in a lathe with a slightly smaller ID than the OD of the lever itself before gently pressing it on.
In reply to cmcgregor :
No pictures found, but it looks like I sent it to RevRico if you want to try and pry it away from him.
In reply to cmcgregor :
That sounds just like I am trying to do! I'll shoot him a text.
I used a momo knob on my old 318ti. Between the rubber "boot" that slipped shaft and the three allen keyed screws that snugged it tight, I never had a problem with it coming loose
RevRico is giving me a good deal on the knob he got from cmcgregor as part of the most recent GRM new years game.
I'm sure I'll end up making my own at some point just to have fun or do something different, but getting this one from Rev checks one thing off my pre-event list without any effort really. With less than two weeks till Carlisle Import & Performance for NICOFest, every little bit helps.
