So, I've taken the plunge and purchased myself a ty250 mono that needs a little work and a few choice mods.

The model I have features the drum brake front, which I'm looking to upgrade to disc. I was wondering if anyone knows of a front end from another more modern bike that will fit straight into the ty's yokes ???

Thanks.

I would leave it as a drum. If it is in good condition and the brake is set up correctly its excellent .

Allright I`ll bite. I rode one for years with it stock. Finally I used the front wheel off a yz125(yes with the z spokes) the master cylinder and caliper. It worked great! And still all yamaha parts easy to come by. Just made a braket for the caliper bolts in aluminum that mounted to the front fork leg. Never welded it just used two clamps.

Thanks for the advice guys. I was considering keeping the original front but when taking the bike out, the front felt very weak with the lever coming all the way back to the bar. Compared to the disc setup on my sherco it's night and day!

Would it be worth while getting new shoes fitted first? Also has anyone used water grooved shoes? As you might be able to tell I'm quite new to the world of ty's!

You cant compare the performance of a drum brake to a disc as you say night and day no more than you can compare an 80's air cooled mono to a Sherco. That would be silly wouldnt it. Usually drum brakes performance is badly affected by wear. Thats wear to the drum, easily rectified by skimming. Wear to the shoes, replace with shoes relined with softer friction material and oversize then skim in a lathe to the exact diamiter of the hub. Finally check the condition of the brake pivot, these often wear and the brake plate also allowing too much play so fit a new pivot or get it machined and get the brake plate machined so they are a snug fit. These are all mods that the "pre65" lads do and if done correctly you can do stoppies with a drum set up properly. Cant want more than that eh?

Three options:

Buy a Pinkie fork bottom and use any modern disc wheel and caliper.

Find a John Shirt casting that converts drum to disc wheel.

Buy a complete TYZ front end and fit.

Options 1 and 2 allow you to go back to standard drum more quickly if required.

You cant compare the performance of a drum brake to a disc as you say night and day no more than you can compare an 80's air cooled mono to a Sherco. That would be silly wouldnt it. Usually drum brakes performance is badly affected by wear. Thats wear to the drum, easily rectified by skimming. Wear to the shoes, replace with shoes relined with softer friction material and oversize then skim in a lathe to the exact diamiter of the hub. Finally check the condition of the brake pivot, these often wear and the brake plate also allowing too much play so fit a new pivot or get it machined and get the brake plate machined so they are a snug fit. These are all mods that the "pre65" lads do and if done correctly you can do stoppies with a drum set up properly. Cant want more than that eh?

Just fit discs and be done with it

Thanks for all the advice guys. I'm leaning towards the full front end swap which will be easiest. I've heard of people putting modern gas gas front ends in. If the fork diameter is the same I couldn't see it being a problem or is this a no no?

Thanks for all the advice guys. I'm leaning towards the full front end swap which will be easiest. I've heard of people putting modern gas gas front ends in. If the fork diameter is the same I couldn't see it being a problem or is this a no no?

Probably easier but gas gas front ends are getting harder to find because the Twinshock and P65 lads are snapping them up along with TY mono ones. If i remembre correctly GG are 38mm but dont know the centres. So either get your yokes machined to 38mm dia or get the GGstem replaced with one to fit the TY and bearings. Either way machining will be involved so would have thought i would be easier to either sort the drum brake out or forget it and ride the sherco if you dont fancy maching parts to fit.

I have to agree, the TY in original form won hundreds of trials and unless you are a super star riding very hard trials I see no real benefit Sorting the drum so it works with new shoes and cable would be simple and very cheap to do.

Metisse, I've think you've hit the nail on the head! I'll probably have more fun fixing the existing setup and learning my new bike (and im certianly no expert rider!)

I was put off the drum front originally at the thought of it not working after going through water, but I'm sure the proper shoes and setup would sort that out.

Having ridden with both I much prefer the disc brake, if you can find someone with a pinky try and get a test ride and then make the decision.

I spent a year trying to find a front end swap, when the far simpler solution was right in my garage.

I fitted the 4 piston caliper, mc, hose from a 2000 gas gas, using a floating bracket on the axle and the torque lug on the leg.

I posted pics and full writeup in the past.

Works GREAT and took about 4 hours to do. and it can be converted back to drum should I ever want to

kcj