1 Car tire on 85 K100 - complete success Sun Sep 04, 2022 11:08 pm
mike jones
active member
For no special reason at all, I decided to expend the money to put a car tire on the back of the 85 K100 rig, since all 3 wheels need replacing anyhow. I had spoken to Claude Stanley a number of years ago, and gave him a shout about adapters. Short story, Claude found an old adapter at his supplier and I ended up with it after a week or so. Since the 4 bolt K100 adapters haven't been used in awhile, Claude couldn't really remember what wheel was used, except it came from Summit Racing, and I would need shorter bolts to attach the adapter to the bike. He did give me a tire size... 165/80R15.
I found some pictures in another forum of the adapter and bolts, plus pics of the wheel used, as mounted. Figuring out the Summit wheel was easy, SUM-531P-5434N19 (150 bucks w/shipping) Sourced all the adapter and wheel bolts locally (just a few bucks). Got a Nexen tire (90 bucks) and had it mounted/balanced at Discount Tire (22 bucks). The tire is dang near the same diameter as the oem size. No re-rigging needed. I don' want to say what I offered Claude for the adapter, but my whole total end of day was a bunch under 800 US dollars.
The whole thing mounted perfectly, with the rear brake caliper nestled inside the wheel with about 1/8 inch clearance, plenty of clearance on the right side to the swingarm, but with a slight interference possibility to the sidestand bracket on the exhaust, which I was not going to remove. I figured a way to space the footpeg bracket outwards with 1/8 inch worth of washers, as the footpeg bracket also positions the exhaust. Problem solved. The problem with the sidestand bracket I had remembered from years past, so looking for it was forefront in my mind, considering I want the bike to be able to be returned to stock.
It is worth noting the exhaust needs to be displaced quite a bit to mount or remove the wheel, or to remove the rear brake caliper.
The tire as positioned is a bit left of stock, which is apparent from a rear look. What I like about the overall solution is that is was thought out to solve all the problems involved... the tire, the wheel, the caliper, everything... even though the solution was old and Claude could not remember everything about it. I could not have started from scratch and done this.
Pics later.
I found some pictures in another forum of the adapter and bolts, plus pics of the wheel used, as mounted. Figuring out the Summit wheel was easy, SUM-531P-5434N19 (150 bucks w/shipping) Sourced all the adapter and wheel bolts locally (just a few bucks). Got a Nexen tire (90 bucks) and had it mounted/balanced at Discount Tire (22 bucks). The tire is dang near the same diameter as the oem size. No re-rigging needed. I don' want to say what I offered Claude for the adapter, but my whole total end of day was a bunch under 800 US dollars.
The whole thing mounted perfectly, with the rear brake caliper nestled inside the wheel with about 1/8 inch clearance, plenty of clearance on the right side to the swingarm, but with a slight interference possibility to the sidestand bracket on the exhaust, which I was not going to remove. I figured a way to space the footpeg bracket outwards with 1/8 inch worth of washers, as the footpeg bracket also positions the exhaust. Problem solved. The problem with the sidestand bracket I had remembered from years past, so looking for it was forefront in my mind, considering I want the bike to be able to be returned to stock.
It is worth noting the exhaust needs to be displaced quite a bit to mount or remove the wheel, or to remove the rear brake caliper.
The tire as positioned is a bit left of stock, which is apparent from a rear look. What I like about the overall solution is that is was thought out to solve all the problems involved... the tire, the wheel, the caliper, everything... even though the solution was old and Claude could not remember everything about it. I could not have started from scratch and done this.
Pics later.