Mismatched brake parts

[Rustynuts]

Hi all, new guy from Scotland here,
Last weekend bought myself a 1977 model at an auto jumble, (swop meet for all you North American cousins) low miles at 27k, and good engine. The front end on this uk spec bike 35mm forks and the later hinged calipers mounted behind the legs. There were no discs included in the sale.wheels are wires with flanged alloy rims, nice.
The seller persuaded me to also but a set of 34mm units with the older iron round type calipers. This set up had original discs which he reckoned I could fit to the 35mm legs.
Two problems have emerged, first the offset of the discs is too great,and second the pair of discs are to small in diameter to engage in the calipers.
I've sussed (found out) that similar discs were available with less of an offset and bought a used pair off fleebay. Thes are still to small . What's going on?
I've noticed a mention on mikessx web site that uk and us bikes have the calipers mounted at differing hights on the fork slider, is this correct, what diameter of discs am I looking for. I'd refer to stick with yam and not mess with modern ones like ducati which might still mess up the offset.
All and any suggestions welcome

 

[Paulrxs650]

Hi Rustynuts, welcome - good to have yet another UK member!
I'm not 100% on the issue you have but I'm sure someone will be along shortly to chip in.

Pop some pics up too

 

[weekendrider]

Rustynuts this thread may help you.
http://www.xs650.com/forum/showthread.php?t=23470&highlight=forks
Welcome to the site.

 

[Rustynuts]

Thanks for the fast replies so far. Looks like I'm looking at for larger 298mm discs, which from some of the info you've pointed me to are uk or Aussie fittings as standard from 77 on. Shame I hastily bought these smaller ones, he ho , need to get them back onto fleebay, someone with a us spec bike , here in the uk will no doubt find a use for them

 

[Paulrxs650]

Yep, I use ebay extensively, handy for the odd stuff - just keep off it after a few pints - unexpected parts arrive at your door!

 

[Rustynuts]

Yeh ,it's addictive , but now its so full of dealers with classified ads, the fun of bidding has just about gone(that's eBay uk we are talking about)good to get rid of stuff tho if you stick to the old fashioned auction style.

 

[650Skull]

Welcome Rustynuts, Do some research on the different models that went to some countries in Europe, i think, ( don't know but there is a niggling feeling), some of them had the large front disk rotor and some the small.

Here is a link to a blog and the owner of it knows a lot about the XS and the european scene, he should be able to help you.

Check where your bike was made for, (vin plate), and i am confused about the 34mm set up, did you buy the whole fork set up or just the rotors and calipers. The early model, 34mm, rotors only come in the large 298mm diameter to my knowledge.

Some pic's would help to identify what you have.

 

[Rustynuts]

Thanks for the various links, I've got it worked out and have fitted a used pair of xs1100 discs which are 298mm with a10 mm offset . sorted as far as I can see. Sorry still no photos yet, as its either pissing with rain or pouring with snow here in Scotland. Roll on our two weeks of summer!!

 

[Paulrxs650]

I here ya!