PD: Primary Drive F103 dimension
- Thread starter Oldhaven
- Start date
I think it's 3/4", But mine is 25 thou under that. Good Luck, Bill.
Ron,
I have a stock F103 at the shop. I can measure it tomorrow. It sets the RFM to the correct alignment with the front wheel. An aluminum spacer is fine once you know the width.
The brake cable did not run there, but I was working on the foot pedal at the time an tucked the cable out of the way.
So, the F103, then the inner primary plate, then a "comma" shaped spacer to step out the footrest plate.
If you do put a spacer in for the footrest that lower bolt (5/16") has a hidden detail. I turned a steel flanged "T" nut that was pushed through the back of the inner primary plate. I think the OD of the shaft was 3/8"and it was drilled and tapped for a 5/16" bolt, which is visible. The hole in the spacer was 3/8", maybe 1/2" and the hole in the footrest was 5/16". I did the same for the gearbox adjuster (lower left). You can see the tapped shaft of the T-nut and a washer and bolt holds it all in place. No through bolt.
The point of all this is to avoid having a bolt go through the inner primary plate. I did that once. After the chain came off when a brake drum shattered the threads of the footrest bolt were damaged and it was not easily removable. It is best to have no threads (or nuts) exposed to the chain.
David
I have a stock F103 at the shop. I can measure it tomorrow. It sets the RFM to the correct alignment with the front wheel. An aluminum spacer is fine once you know the width.
The brake cable did not run there, but I was working on the foot pedal at the time an tucked the cable out of the way.
So, the F103, then the inner primary plate, then a "comma" shaped spacer to step out the footrest plate.
If you do put a spacer in for the footrest that lower bolt (5/16") has a hidden detail. I turned a steel flanged "T" nut that was pushed through the back of the inner primary plate. I think the OD of the shaft was 3/8"and it was drilled and tapped for a 5/16" bolt, which is visible. The hole in the spacer was 3/8", maybe 1/2" and the hole in the footrest was 5/16". I did the same for the gearbox adjuster (lower left). You can see the tapped shaft of the T-nut and a washer and bolt holds it all in place. No through bolt.
The point of all this is to avoid having a bolt go through the inner primary plate. I did that once. After the chain came off when a brake drum shattered the threads of the footrest bolt were damaged and it was not easily removable. It is best to have no threads (or nuts) exposed to the chain.
David
Thanks Bill and David. I wanted to make sure the alignment was correct by using the right thickness, since I had supposed F103 was the datum. David, if you can confirm Bill's measurement I am good to go. For a spacer I may try to copy the F103 shape extending up toward the front to the four holes in the inner primary.
The t-nuts you describe sound a lot like rivnuts. I used some stainless ones on an aluminum boat to secure the deck and was pretty pleased. I was sure to use non corroding anti seize in them since if they come loose in the substrate due to seized threads they can be awful to remove.
The t-nuts you describe sound a lot like rivnuts. I used some stainless ones on an aluminum boat to secure the deck and was pretty pleased. I was sure to use non corroding anti seize in them since if they come loose in the substrate due to seized threads they can be awful to remove.
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