87 WR430 disc brake conversion

[Darrel78]

Finally getting started on my disc brake conversion for the rear brake. This conversion uses a wheel from a Husqvarna 360, mid 90's vintage. I choose to use only 2 bearings in this wheel rather than three. I'll use the bearings from the 430 as the OD is the same. I'll machine spacers to set the bearings to the outside of the hub.

 

[Darrel78]

Machining the spacers. These drop in and set the bearings to the proper position in the hub. This example needed one at 0.340 on the sprocket side and one at 0.060 on the brake side. These spacers put the bearings to the outside of the hub while allowing room for the seals (yet to be sourced).

 

[Darrel78]

More pics of the bearing fitments. Using these bearings allows no maching of the swingarm or axle.

 

[Darrel78]

More pics

 

[Darrel78]

And more

 

[Darrel78]

Final arrangement. I machined a brake anchor to be welded to the swingarm.

 

[Darrel78]

 

[Darrel78]

 

[Darrel78]

I hope to get the brake anchor welded this week. More pics later.

 

[justintendo]

looks promising. did you decide on how to mount the master and reservoir?

 

[Darrel78]

Not yet. I'll figure that out pretty quick. Not sure how to connect the brake lever to the master cylinder yet either. I've got to learn how to think these things through...

 

[justintendo]

thinking things through before doing major machine work? naw...

 

[Norman Foley]

Take a look at an early 90's 4T 350 or 610, as it's pretty much the same frame and swing arm.

 

[fran...k.]

I agree with Norman, go one step further one should source parts from the four stroke bikes for these conversions. The swingarm 85-88 or so will fit into the frame of a 1999 model te410. I do not know how the linkage would work out if and over the years but using the more modern swingarm would allow use of the larger axle. How is the offset of a two stroke wheel sprocket vs what came on your bike when the rim is centered? Is any spoke adjustment needed or is it going to be a bit far for that?

 

[Darrel78]

Thanks, Fran...k. I'm going to reuse my old rim so as to keep them matched front and back. I used the original sprocket as my datum line and made my spacers to suit the new wheel. I'll lace the wheel so as to center the tire in the space I've got. I don't foresee any issues with staying with the 15mm axle as the stock bikes didn't seem to have issues on this account. As it turns out my bearing spacing with the new wheel is only 0.2 different from the old; this in the delta in hub widths.

 

[Norman Foley]

I've never checked myself, as I never had the need. My '87 430WR broke the left side case, long ago and got parted out. But I do know looking at my '93 WXC350, a lot of stuff is almost identical. If you started with the wheel from a '92 or 93 4T, you might have been suprised at, how little you had to do spacer wise. Since the single cam 4T Italian frame is the same as your monoshock 2T Swedish one, you should source your rear brake parts from the 4T and look at how it all mounts to the frame. This might save you some time and head scratching.

 

[Darrel78]

Thanks, Norman. That's good information!

 

[2premo]

Take a look at an early 90's 4T 350 or 610, as it's pretty much the same frame and swing arm.

that is the route I was taking, 92 610 swingarm, the linkage is offset for sure, did not have a chance to review the ratios jus yet either, advantage with the 92 swingarm is the grease fitting as a bonus

 

[Darrel78]

Welding complete.

 

[Darrel78]

Swinger bearings were making a grinding noise...