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spoked rear wheel

This is just great ... I'm doing the same conversion for my CB900F.. Thx..

I've measured the front hub to.. and I've come up with these dimensions..

The inner dimension of the conversion ring to Ø102mm (measured the wheelhub to be 100mm, but added 2mm for fitting)
Boltcircle Ø122mm (the above measurement plus your experience)

That seems to be correct - But I only checked it so far by calculating the distance between two bolts and then measuring it to see if it checked out and it did :) ...

I'll make some CAD-files and print them to scale to check if the measurements are correct - I'll get back soon :)
 
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Hi SmaRTrxxv,

Thank you for your interest in this subject. In the interest of every reader of this subject, can I please advise you to clarify your measurements? You mention an inner dimension. Inner dimension of what? Bolt circle of what? If you can, please make a sketch, so that every reader can benefit from your experience. If I can be of any help, please let me know. Right now I'm in a project to modify a Moto Guzzi, but I'm still interested in this subject.

Thanks in advance, and good luck with your experiment
 
Well.. I can see know that it is bit messy what I wrote.. it's the inner dimension of the adapter/conversion ring..

The boltcircle of the 5 bolts that will hold the conversion ring in place at the wheel hub..

Thx for offering your help - right now I believe I'm fine though..

I will provide a sketch from AutoCAD when I get it done :)
 
Hope this clarifies it a bit..

CB-SPOKE-FLANGES2.jpg
 
Hi, thats a drawing I stole on the internet and then added my numbers to it.
I do have a CAD-drawing of the spoke conversion rings I'm making for my self though.

But I'm currently working in Korea and the drawings are at my friends PC back in Denmark. I'm a Mac-user and I don't have CAD-software my self (very pricy!!!!) ... But I'll post the drawings as picture and the CAD-file format, when I get back home, but that might not be until November this year.
 
Hi guys,

I'm a new member and have recently bought myself a 78 cb750ss (with the much disliked comstar rims).

Anyway, I have defiantly missed the boat on this conversation, but I'm hopeful that someone might still be lurking.

I will be converting the comstar to spokes using the spoke rings and I just wanted to gather some more information.

I have CAD'ed up the rear spoke rings using fingerprice's method, and am just about to measure up my front hub.

Just want to see how the rings are holding up and if there were any design changes from then to now?

I'll thank anyone in advance. Dennis.
 
Hi guys,

I'm a new member and have recently bought myself a 78 cb750ss (with the much disliked comstar rims).

Anyway, I have defiantly missed the boat on this conversation, but I'm hopeful that someone might still be lurking.

I will be converting the comstar to spokes using the spoke rings and I just wanted to gather some more information.

I have CAD'ed up the rear spoke rings using fingerprice's method, and am just about to measure up my front hub.

Just want to see how the rings are holding up and if there were any design changes from then to now?

I'll thank anyone in advance. Dennis.


Hi Dennis,
I suggest that you buy a set of front wheel spokes for a 750K, measure the spoke length, and use the spoke length formula, to work backwards.
Use the inner ring diameter and the bolt circle diameter of the earlier post.
If you have some measurements, I will help you out. The width of the wheel hub is also needed.
Good luck.
 
Ok thanks, I was looking at some pics of the rings- do the spoke holes have to be slightly offset from the bolt holes on the opposite ring on the hub? Or can the spoke rings be drilled identically and rotated around to the next bolt hole when fitting? I have noticed it looks like they are slightly offset. There is a local bloke near me who I will be buying the spokes and rims from but he is away for a week or so.
 
Thanks for the link, I'm aware that the completed product is just one easy click away, but the cost for me in Australia is $500+ with the Aud/Usd $ conversion and postage. So I'd rather have a go and learn something myself. Although I'm jumping into this blind and need all the help I can get.
 
Thanks for the link, I'm aware that the completed product is just one easy click away, but the cost for me in Australia is $500+ with the Aud/Usd $ conversion and postage. So I'd rather have a go and learn something myself. Although I'm jumping into this blind and need all the help I can get.


Did you check this page where he discusses a lot of the development process?

http://motosynthesis.blogspot.com/p/products.html
 
Yeah I have been through all of that. No where does he explain the reasoning behind the layout. And fair enough too, if you want to make money from making these, you can't give away all the secrets. This conversation was the closest I have come to getting the answers, so I just thought I'd try with a few questions.

Thanks.
 
Ok thanks, I was looking at some pics of the rings- do the spoke holes have to be slightly offset from the bolt holes on the opposite ring on the hub? Or can the spoke rings be drilled identically and rotated around to the next bolt hole when fitting? I have noticed it looks like they are slightly offset. There is a local bloke near me who I will be buying the spokes and rims from but he is away for a week or so.

Dennis,

The offset between the bolt holes and the spoke holes is there for a reason. The bolts that hold the rings are mounted in extended material on the hub. If you don't keep this offset, you won't be able to mount all your spokes, because of the extended material on the hub. If you see the drawing of the rear spoke rings, you will see that one drawing is the mirror image of the other. So yes, they can be drilled identically and rotated.

Cheers
 
Dennis

I am like you a long way and expensive postage from motosynthesis. Would you be able to provide me with you CAD files so I can get them cut in NZ.

Cheers
Bruce
 
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