Cardinell

Not sure if this is an FC specific issue, or even an RX7 specific issue, but figured I'd throw it up here to see if anyone has encountered this issue or knows of a solution

Long story short, trying to install a Momo steering wheel with an NRG hub. Hub went on, no issues, and the wheel bolts up to the hub, no issues

The problem I'm having is with the horn button. When trying to install the horn onto the wheel, the bottom of the horn is making contact with the threads on the steering column, preventing the horn from seating all the way. Once the horn makes contact, I've still got about a ½" gap before it clicks into place.

Has anyone run into this before? Am I doing something wrong? Any advice is much appreciated





For reference this is the specific style of horn button I'm using. Momo has a few different styles, but this one has a spade connector for power, and a wire off to the side that grounds it to a ring that sandwiches between the wheel and the hub:



Ground ring

WondrousBread

I don't have any input on the horn button issue, but one thing you should check is the clearance from the wheel to the turn signal stalk. With a similar Momo wheel and the NRG short hub, mine was basically colliding, so I had to get an extension to push it outward a few inches.

Obviously you don't want to be in a situation where turning the wheel makes your knuckles hit the turn signal stalk every time.

I mention this because that same extension basically solves your issue, so if you have the turn-signal clearance problem you can kill two birds with one stone.

Cardinell

Duh, why didn't I think of that. Ordered a 1/2" spacer, should arrive tomorrow. Will update once it's installed. Hopefully that fixes the issue. My concern is that a 1" spacer will bring the wheel too close to me

Cardinell

Update on this. Hub spacer fixed the issue of the horn hitting the steering column, but another issue has presented itself. The ground ring that Momo sells does not fit inside the spacer, as the diameter of the collar on the back side of the ring is slightly too large. I've order a different brand of ground ring off eBay that says it works with momo, so hopefully that will fix it. Will update again soon

ncs201

I've had this issue too. I took a spare aluminium part and machined a spacer. It is about 8mm thick so the steering wheel does not stand out too much. Works perfectly fine. Only issue is that my horn does not work, but i think its the horn itself and not the button.

Cardinell

Just another update:
I was able to get everything put together and working. The issue with the ground ring that Momo provides is there's a raised lip on the hub side, and it clashes with the spacer and won't sit flush. I was able to find a ground ring for Momo horn buttons on ebay that is flat on the hub side, so it sits perfectly.



Issue I'm running into now is with the trim pieces for the steering column. They don't fit properly with the hub and I had to take them off in order to get the steering wheel to rotate without any resistance. Anyone run into this issue with the NRG hub?

WondrousBread

I have. You need to cut the plastics to accommodate the hub. It's irritating that NRG doesn't mention this at all before purchasing, but I assume it's because they designed their hub for an FD / Miata / 323, or something else that has the same spline pattern. Then they probably just assumed it would fit the Rx7 as it has the same splines and listed it accordingly.

https://www.rx7club.com/build-thread.../#post12511636

Cardinell

That is so dumb. Well, the column trim was cracked on my car anyway. Guess it's time to order it new from Mazda, or post something in the classifieds. Appreciate the insight!