XV Disc

wally · Posted: May 17, 2009, 10:50 pm Post subject: XV Disc

Ha Guys
How do you think this looks
I am going to take of the two existing discs on my cafe & fit this left XV disc I picked up, to my right side what do yoy think
Paint it black of course
The two discs at present look all to much I think one will look better
I am fitting to the ride becourse of disc & caliper scrubing problems on the left side

Any comments

yamaman · Posted: May 18, 2009, 1:36 am Post subject: Re: XV Disc

Yeah, looks pretty good Wally. Your going to probably need a master cyl change to go with it though. Vintage brake have a good worksheet on their site, tells you what master cyl to what calliper is best!

wally · Posted: May 18, 2009, 3:40 am Post subject: Re: XV Disc

I have on this bike the 16mm Mikes master cylinder why cant Im just use this one with one hose

ghostyder · Posted: May 18, 2009, 4:20 am Post subject: Re: XV Disc

im running a master cylinder off a chinese mini bike. seems to work just fine to me.

xsleo · Posted: May 18, 2009, 11:15 am Post subject: Re: XV Disc

With a m/c with to large a bore size the brakes will feel wooden, no feel and pull to hard. one with a few mm's smaller will have more power but lever travel will increase, if too smaal the lever will travel so far that the lever will hit the grip before they work. A 11mm bore is about right for one of the later style calipers. You need to balance the amount of fluid that the caliper needs to the amount the m/c pushes.

wally · Posted: May 18, 2009, 4:35 pm Post subject: Re: XV Disc

xsleo wrote:

With a m/c with to large a bore size the brakes will feel wooden, no feel and pull to hard. one with a few mm's smaller will have more power but lever travel will increase, if too smaal the lever will travel so far that the lever will hit the grip before they work. A 11mm bore is about right for one of the later style calipers. You need to balance the amount of fluid that the caliper needs to the amount the m/c pushes.

Mike states the 16mm master cylinder is good for both

Master Cylinder Assembly - 16mm bore. - Recommended for late dual disc Front
brakes on 1977-84 XS650's or single front disc brake (1972-76 650's). Yamaha
OEM type. Complete with brake lever, brake light switch, banjo bolt and washers

yamaman · Posted: May 18, 2009, 11:31 pm Post subject: Re: XV Disc

Yes Wally, but your going for a '77 - '84 single disc! So Mikes doesn't recommend that.

The old callipers were 48mm cast iron TWIN piston. The newer callipers are 40mm SINGLE piston.

You want to change from 2 active pistons to 1. Ideal master cyl for that would be 11 or 12mm according to the Vintage Brake chart:

www.vintagebrake.com/m...linder.htm

wally · Posted: May 20, 2009, 1:40 am Post subject: Re: XV Disc

Looks OK YES!

yamaman · Posted: May 21, 2009, 8:16 am Post subject: Re: XV Disc

Looks cool Wally, how do the brakes feel?

wally · Posted: May 21, 2009, 6:00 pm Post subject: Re: XV Disc

I have only rode around the block so far as its been pissing down here for days
So on that little ride brakes the brake lever needed a little more presure to stop me but I had two discs before, Bit of scrubing on the top of the caliper can these disca have the outer circumference of a disc be cut down

Made a small plate to cover the old caliper mounting points later I think Ill have made a complete shroud to go over this, same shap as the single plate in pic

What Happened to 650rider.com?

Yamaha xs650