THE BIGWHEEL THREAD!!! Yamaha BW350, BW200

[Shercoman]

Originally Posted by vroom_vroom

is there any way to do a disc conversion without replacing the front forks? they seem to bee few and far between for the tri z forks

As a tool and die maker I say this is possible by removing the brake disc from the hub,machining an aluminum adapter to mount a disc and machining a caliper mount that would replace the current drum brake backing plate assembly,act as a wheel spacer and use the lug on the fork for anti rotation.
Yes,it could be done with some custom parts.

If there is an interest in this I could work it out.

Choosing a common disc and caliper would be the first step.
I am converting my BW to disc but I am using a CR/XR disc and caliper on TriZ forks.

[vroom_vroom]

Not sure the cost to pull off the front fork conversion but it seems to me that the conversion would be worth some money

[Mr. BigWheel]

There is always a bit of interest in a front disc for the BWs. I would estimate the costs of converting to a Tri Z front end as follows:

Forks - $100
Axle - $20
Brakes - $100
Hub - $35
Rotor - $20
Triple Clamp - $50

You could be a patient, smart shopper and get all of those items considerably cheaper, but that takes some time.

That's a total of $325. Like all estimates, it is probably safe to double that number to cover all of the variables.

For example; 1) Are the bearings in the used hub you bought usable?
2) Will you need new brake pads?
3) You will probably need fork seals and possibly bushings
4) Are you using '86 Tri Z forks? - they usually go for more $
5) Did you get all of the hardware or will you need new stuff?
6) Does the caliper need to be resealed?

You can use your old BW fender with some spacers, otherwise a new Maier Tri Z is about $120 on eBay.

Shipping is going to add 10 to 20%.

For all of that money you get a 25 year old brake system and a 25 year old right-side-up fork. The forks are better (longer travel, somewhat better dampening and larger diameter tubes) The brakes are better (what wouldn't be better?) and it all bolts together very easily.

Is it worth it? Probably not.

I really like having the Z fork but a Shercoman-modded original fork would be a very close second.

Regards,

Mr. BigWheel

[WR450FADVn]

did alittle bit to the old fat kitty over the weekend. new front fender, 6 pack holder, and trailer setup.

[Mr. BigWheel]

WR450FADVn,

I think you could honestly label the rack as a half-rack holder. But it's completely superseded by that keg hauling trailer.

Why does a Fatcat have two cables running to the rear brake?



Further thoughts on the front disc brake setup:

Perhaps the easiest modification would use a TW200 lower fork tube. This would be the left side:





There is already a caliper mount so there would be no machining for the fork tube.

The TW caliper and mounting bracket are bolt-on parts that are in plentiful supply.

The inner fork tubes are 33mm and slide right into the BW triple clamps.

The axle mounts are in the same location and there would be no change in the steering geometry.

The forks are the same length, so there would be no need to get a longer rear shock as there is on the Tri Z conversion.

The major obstacle would be the rotor mounting point and setting up spacers to keep everything centered.

That is my academic treatise on the subject. Of course, I am utterly worthless as far as enacting any such project.

Regards,

Mr. BigWheel

[vroom_vroom]

So guys I have a big(wheel) problem

[vroom_vroom]

The big wheel will not kick over, I changed the oil And three I. A new filter and now it will not start. I had a friend helping me and he put both full quarts of oil in the bike before I could get to it and now I am not getting power to the coil back and it's driving me nuts, it ran just fine two days ago and now nothing. How would over filling the oil make the cool go without power?

[RebelYell]

Maybe the ls vegas heat burnt it up? Did you accidently pull the coil wire off,make sure coil and plug wires are secure,did you break a ground off the coil wire etc?Coil aare like fuel pumps tho one day they work fine the next minute your motoring along and kapow the bitch just quits.usually a bad coil when it gets hot it will start missing bad before it totally quits,wont restart when it coold down it fires fine till it gets hot again.maybe cdi is bad if the other stuff checks out,not sure if bike has fuses but check them too

[vroom_vroom]

I'm not getting power to the coil and can't figure out why not

[Shercoman]

Originally Posted by Mr. BigWheel

WR450FADVn,

I think you could honestly label the rack as a half-rack holder. But it's completely superseded by that keg hauling trailer.

Why does a Fatcat have two cables running to the rear brake?



Further thoughts on the front disc brake setup:

Perhaps the easiest modification would use a TW200 lower fork tube. This would be the left side:





There is already a caliper mount so there would be no machining for the fork tube.

The TW caliper and mounting bracket are bolt-on parts that are in plentiful supply.

The inner fork tubes are 33mm and slide right into the BW triple clamps.

The axle mounts are in the same location and there would be no change in the steering geometry.

The forks are the same length, so there would be no need to get a longer rear shock as there is on the Tri Z conversion.

The major obstacle would be the rotor mounting point and setting up spacers to keep everything centered.

That is my academic treatise on the subject. Of course, I am utterly worthless as far as enacting any such project.

Regards,

Mr. BigWheel

This looks like a good way to go.
Mounting the caliper is the hard part of this project so that is taken care of.

Machining a disc mount to adapt to the original hub would be the easier part.
Would a TriZ hub work in these forks? That would simplify thing even further but the spacing might be an issue.

[WR450FADVn]

Originally Posted by Mr. BigWheel

WR450FADVn,

I think you could honestly label the rack as a half-rack holder. But it's completely superseded by that keg hauling trailer.

Why does a Fatcat have two cables running to the rear brake?


Regards,

Mr. BigWheel

one for the hand brake and one for the foot brake. the hand brake even has a parking brake made into it

[Mr. BigWheel]

I guess the distinction between the two is that the BigWheel is a three-wheeler with two wheels while the Fatcat is a four-wheeler with two wheels.

Shercoman,

I believe that the Tri Z axle has a slightly smaller diameter than the BW. Perhaps the Z hub could be used on the BW axle if there are bearings that have the hub's I.D. and the axle's O.D.

I'm on the road until the weekend but I will confirm that observation when I get home. I'll put a BW front end together and fit a Tri Z hub for some pictures so you can see what kind of clearance issues there are.

Regards,

Mr. BigWheel

[epix1718]

Got the motor split, now just trying to get the damn circlip off the main axle!!! Been trying with flat head and small pliers but just can't get it.. gonna try again later when I am less frustrated.

[Shercoman]

Originally Posted by epix1718

Got the motor split, now just trying to get the damn circlip off the main axle!!! Been trying with flat head and small pliers but just can't get it.. gonna try again later when I am less frustrated.

Save yourself a lot of frustration and buy a pair of snap ring pliers.
Less time cussing and more time rebuilding!

[Duster11]

I need to remove a bw350 airbox to clean it up. Previous owners did some messy stuff to it (see pic). I am going to go thru the carb too so I figure this would be a good first step. Can anyone walk me thru this getting the airbox out?

Thanks,
duster11