Hi Folks,
as already indicated, I have done a conversion to 17". In contrary to all others here I will continue to use the 280mm brake disks in the front. The reason for this decision was, that I have already spend some money for the full floating disks not long ago. It also saves the money for the rest, means new calipers and so on...
The brake force is still more than enough, specially for normal road use. We are not riding a 180HP powered bike.... When you enter race tracks, it could be a different thing. If you use the original disks, it might be also more useful to change towards 320.

This is, how the adapter looks like:


A friend did the machining... Also we machined a new pivot for the front wheel, this saved me from changing towards other bearings and/or machining carrier of the bearing in the rim. Will show a picture of the pivot later. I am still working on the speedo drive. It has to be milled down a little, but the angle of the cable is a bit too flat for the (more narrow) 280 disk.
Will also show a picture later.
I have only powerpoints-files with drawings of the adapter and the pivot, if someone wants it...

Cheers
Felix

PS: I know that there are some screws missing, I just assembled it quickly for the fotos. I will not drive like shown here!!!

Felix,

I can upload the files here. I still have a question though regarding the offest of the brake disc (12mm stated in your ppt file and 10mm mentioned on brake disc manufacturer`s homepages).

G.

Gerhard,

uups.
Good question.... but sorry, I cannot answer. I installed the wheel with speedo drive, fixed the disks in the caliper and measured the distance with a slide gauge as precise as possible. I went for 12,5mm, but the difference of 2,5mm is a lot.
I haven´t looked for a hint in the web. Do you have one?
Isn´t this a matter of the rim, too?

May it be caused by a difference in the design of the break disks? I have the old ones still here, I will check tomorrow... also the rim dimension on the center.

Felix

Hi Felix,

Nice job, on the adapters!

Would your friend be prepared to machine up another set?! (for a reasonable price)

Cheers,

Alf

@Alf: Mmmm, let me check it. Since it was machined in the company where my friend is employed (and their business is NOT in motorbike parts), we cannot offer a "series" production. For one pair...lets see.
Did I get this correct, you have the M1R fork? I hope that all positions/distances would be the same as at the original fork. Otherwise you´re lost....
But on the other hand, one caliper and one 320 disk do not cost a fortune? If you are looking for someone which could be interested to purchase a pair of full floating 280 disks, I have a candidate over here....

@Gerhard: Good point, that could be the reason .
I do not have 4piston calipers here, so I cannot verify. But this is the most reasonable explanation.

Ciao
Felix

here are your files:

http://www.box.net/shared/mij5pzbz38

one more question. The material thickness is 5mm also there were the threads for the brake discs are. Isn`t that a bit on the thin side considering also the design with the arms and do your adapters have a centering edge for the brake disc ?

these are the same adapters (different design) that were part of a complete 17" conversion set on ebay

Hi Felix,

I would consider selling the full floating discs, but I am trying to keep all the original parts for the bike as well as doing the conversion. I will be keeping the original wheels, calipers, etc. since I have a brand new set of original Michelin tyres as well which have not even been fitted. Probably useless for any performance riding due to age/hardness, but original is always good!

Also, I think the single disc model that I have fitted has a different offset to the double sided, so I will either have to get adapters for the 280mm discs or get a pair of 320s and an extra caliper. The original wheels run in the M1R forks, so I guess the adapters are made to place the discs in the right position. Anyhow, the caliper may also be shimmed a little for central positioning over the disc.

Cheers,

Alf

The thickness of 5mm is defineteley not enough, thats true. We machined NOT 5mm... I must recheck, I think its 10mm.
Material, we took a ST52 steel, or slightly better. I was told by a person from TÜV, that they "do not like" Alu since they do not know the quality.
Gerhard, I don´t have a centering edge. Is it necessary?

Cheers
Felix

Felix, I`m referring to the second picture of your ppt file. There it says material thickness 5mm.
Regarding centering edge. Good question. I`m not a technical designer, but as the wheels have one, the sprocket carrier also and other aftermarket adapters have it I would have implemented it, too. It may take a little stress away from the 6 mounting bolts. But that`s just gut feeling.

This pic is from my Paso repair:



This really has no big purpose. The rotor drops right over and has some slight movement. It probably keeps the rotor centered to control any run out. I don't know how much movement the bolts will allow tho.

Hi Manxman,

I know your original post was made a long time ago, but im interested in following your design and using original forks, brake rotors and a 900ss wheel. did your adaptors and speedo drive end up working out ok?

anyone else have any observations/photos on 17" conversions?

cheers

Sean

Hi customhead,

here`s is my conversation:

viewtopic.php?f=1&t=1779

Fork, frontwheel, brakings all ST2. Rearrim and brake from an early Monster with 17mm axle.

@Felix - wusste gar nicht daß Du jez 17er hast!

Greetings to Gerhardt and Felix and all others...

Hi helge-siens
I have a rear 17" brembo rim from a 750 ss ducati - 4.5" which i now want to replace the 16" rear rim on my sport. Do you have details of the spacers you used to fit the 17" rim including how you got the sprocket to line up?
cheers