BIKEMOTORPARTS.COM...Anyone Using?

[Porkchop]

You're into doing the math on all this stuff, huh ? I do the same thing sometimes. I did not understand the thing about the free wheeling on the 1.25" roller until James explained it to me. I don't know that it's a big advantage, but now I know what it does ! Keep me/us posted on your kit.
Thanks !

You're not trying to fit a square peg into a round hole are you ? Just kidding !BMP kit might not be the best in the world, but it does looks descent and simple. I'm looking for quality and low price. I'm not familiar with the Staton I've been reading about. I'm just going to use the factory set up when I receive it. Good luck Pal !

 

[Happy Valley]

OK good, thanks for your early impressions.

I was wondering if there would be a tendency for the bent steel channel to develop flex and distort at all with use; being half as thick and with 50% less surface for the bearings to seat in if the bearings might ever become loose, spin or out of alignment wearing excessively.

The DE drives I have are new and they are made with very rigid 3/16" 6061 aluminum.

 

[Rich 240]

I would say that steel vs aluminum is probably a manufacturer's preference.
One manufacturer may be more comfortable machining aluminum and the other steel. Maybe based on their manufacturing equipment. Each manufacturer would choose material appropriate for the application hence a thinner steel plate vs a thicker aluminum extrusion would be logical because it takes somewhat more volume of aluminum to provide the same strength as steel. The aluminum extrusion would certainly be more rigid than the steel. In this application however, the steel would also seem to provide adequate strength to perform well. I don't believe a sheet of bent aluminum of an equal thickness of the bent steel plate would be as strong so thicker aluminum extrusion makes sense to me. Bending aluminum that thick isn't really practical when a formed piece is available instead.
Adequate support of the various motors and the different mounting solutions the manufacturers designed may have been influenced the choice of steel or aluminum, too. BMP specifies their kit fits the wider bolt pattern of the larger 76mm clutch on a smaller choice of engines while staton manufactured their kit and adaptors to be able to accept engines with smaller clutches and mounting bolt configurations which may have influenced their decision to use aluminum vs steel for their mounting bracket.

 

[Happy Valley]

Maybe there is a little "flex" engineered into the overall package as a way of dynamically letting things settle into position and dampen some of the vibration and shearing forces present in the mechanical processes.

From experience with the China Girl engine mounting, sometimes rigid is not best. I sheared a number of motor studs and noticed the front bolt mount was also showing signs of shearing.

Somewhat apples and oranges. HTs have excessive vibration from unbalanced crankshafts and the engine block rigidly mounted to down/seat tubes.

While there are shortcomings in rack mounted friction drives, excessive vibration isn't usually one of them. Driving off the tire acts like a big, pneumatic bumper. Rack mounts also often employ the better quality Japanese utility engines.

Torsional flex in the mount can create problems in maintaining exact alignment of the drive spindle. Tire wear is one of the major caveats often cited about friction drive and after much experience I'm convinced that alignment is one of the main contributors.

 

[5-7HEAVEN]

You're into doing the math on all this stuff, huh ? I do the same thing sometimes. I did not understand the thing about the free wheeling on the 1.25" roller until James explained it to me. I don't know that it's a big advantage, but now I know what it does ! Keep me/us posted on your kit.
Thanks !

The math gets me in the ballpark, then trial and error gets the job done.

The freewheeling roller SEEMS to have an advantage. It stops the roller and clutch drum from turning. HOWEVER, methinks most of the resistance drag comes from the ROLLER, freewheeling or not, digging into the tire.

Porkchop, square peg in round hole? If you're a hotrodder using aftermarket parts, the square peg WILL! be modified to fit the round hole.

When I installed the first TS aluminum exhaust flange onto my Mitsubishi engine, I had to make it fit. The flange was made for a G62 or GP460 engine. Elongating the bolt holes and bigger bolts and the pipe slipped in...after sawing off the pipe's mounting bracket.

When I ordered the same flange for my second Mits engine, I elongated the holes and the powerpipe wouldn't slip in. So It took an hour of filing the flange's port before it fit.

 

[Happy Valley]

I would say that steel vs aluminum is probably a manufacturer's preference.
One manufacturer may be more comfortable machining aluminum and the other steel. Maybe based on their manufacturing equipment. The aluminum extrusion would certainly be more rigid than the steel. In this application however, the steel would also seem to provide adequate strength to perform well.

Not sure if the fact was missed that BMP used to use aluminum channel. I have one as do I have at least one of the other two FDs mentioned.

I can't speak to what drives a particular manufacturers preferences though I'd suspect making a profit has to be on the short list. I can speak to what I know and what my preferences are....particularly in regards to quality and bang for my buck.

I do know Staton and DE do their own machining and maintain their own machine shops and tooling.

I do know BMP does not as it was explained to me once why an order of mine was slow; they were waiting for the pieces to come from the contract shop.

Later I noticed they went to the bent steel. I'm sure that is cheaper to manufacture in material costs alone, yet the price has remained the same.

Now, one might hold an opinion of what would be adequate, but I'll keep my own counsel on that. I have a product that I thought was better than adequate before and I'm perceiving a downgrade on that, hence my inquiry into certain characteristics of the present offerings.

 

[Rich 240]

Not having experience with the BMP kit containing the aluminum extrusion, I have no basis for comparison and leave that to those who have experience with both.

Staton and DE have both been at this a long time and have probably experimented with a variety of materials and settled where we find them today with what they believe to be the best combination of ingredients both from a quality and profitability standpoint.

Alignment and tire wear on my machine (bent steel) seem to be spot on. My tires were brand new with the little flashing left from molding the tire still on them. After about 100 or so miles, this little membrane of rubber has scrubbed off and the tire is running very clean with no indication of slippage. Looks like normal wear.

I really notice very little drag by the one way roller. Today I rode maybe 1/2 mile (on the flat) through a "quiet zone" with the engine off and the roller in contact with the tire and noticed no appreciable difference in pedal effort just a tiny "whir" letting me know the roller was touching the tire at about 7 to 10 mph.

One thing I wonder about is if anyone is manufacturing the free wheel one way rotor in other than 1.25" size.

I wonder if it is possible to "sleeve" one of these rollers somehow so that the diameter of the roller could be increased without having to remove the axle, bearings etc.

I'm a designer, not an engineer or machinist and I can picture a couple of ways this could be accomplished.

So if anyone has a desire to explore this I'd be more than happy to draw up what I think might work and a machinist/engineer could see if it was feasible.

From what I've read here, that seems to be something that friction drive systems could benefit from.

 

[5-7HEAVEN]

Happy, thanks for your feedback.

Rich240 I COULD use a smaller diameter one-way roller, 1.125" in size. Since it would cost me $32 to ship Staton's $33 roller to me, the local machinist could probably cut my BMP spindle down to size for less $$.

I am a full-blooded hotrodder. I 've been one ever since I picked up my first "Rod & Custom" magazine 50 years ago and wrenched my first bicycle and car.

Just can't leave well enough alone. All my vehicles were modified except the wife's cars. Mitsubishi engines never remained stock, and neither will GP460's.

The BMP steel engine channel WILL suffice. They can so easily be strengthened everywhere with cross-braces.

The BMP kit looks durable but some Staton parts are bulletproof. The solid clutch drum spacer is gorrilla-strength compared to BMP's aluminum tubing spacers. I'm using the stronger spacer but taking a big hint from BMP. Their shorter spacers result in 56% more clutch surface area than Staton spacers allow.

Sooo I will have the Staton spacer machined .3125" off the lip. This will allow the clutch drum to penetrate deeper into the clutch housing and produce over 46% increase in clutch surface area. Shortening the spacer should also make a stronger connection to engine, clutch and channel.

It's like replacing a 10.5" automobile clutch with a 12.75" clutch.

The BMP kit looks strong. However, if the GP460 wants to twist things up, I ordered an extra pair of struts to brace from channel housing to bike frame.

 

[Rich 240]

Sounds like you are putting together the ideal setup pulling what you need from the parts bins of the various kits and then integrating them together for a stouter package than any of the kits could provide from stock. True to your hot rodding roots.

I think your fifty years of wrenching has probably given you that intuitive sense of knowing where you need to beef things up.

My little Honda motor may do just fine hanging off those little spacers but your powerful engine will probably fare much better using the bullet proof Staton mount and overall performance certainly should be better getting more "meat" of the clutch biting into the surface of the clutch bell by machining that Staton part.

 

[5-7HEAVEN]

BMP And Front Friction Drive!

James the owner from BMP returned my call. I told him I was interested in front friction drive for a project I'm working on. He apologized, said he didn't have front drive.

I mentioned that his rear friction drive housing could be EASILY modified to fit front ANNND rear tire. All it would take would be to drill the four engine mounting holes on BOTH sides of the engine channel. Then the two bolt holes for the front U-bracket AND the holes for the rear support rods would have to be drilled on the opposite sides of the housing!

VOILA!!! A friction drive kit to mount on either front or rear tire!!

James was VERY interested in my idea. Don't be surprised if a NEW front friction drive kit becomes available from BMP in the future!

By the same token, Staton's rear friction drive kit can also be retrofitted for front friction drive. This vendor offers a front friction drive available, which could ALSO be modified for rear drive use.

James suggested that the new engine bolt holes need to be precisely drilled, and cardboard templates could be made.

I stated that I was going to order a SECOND kit from him today and send it to a machine shop. Later I realized that my FIRST BMP kit I had ordered will be my template. The engine channels will align with great precision, using the existing 1.375" bearing as a pilot bearing. It would slip into BOTH .125" steel housings while I mark the engine mounting holes.

The new modified BMP drive kit will now have all mounts for front drive. THENNN, I will drill the rear engine channel likewise.

That way, BOTH friction drive kits will be universal and mount on either tire.

This is such a FANTASTIC idea! When I have time, I'll do the same drilling mods to my Staton drive kits.

This way, ALL FOUR of my friction drives will be interchangeable.

MOST of the parts are interchangeable between Staton and BMP kits. However the BMP utilizaes a .50" diameter driveshaft; its rollers slip on and lock onto the shaft. Its shaft and clutch drum are threaded for 8mm, while Staton drums and rollers are US threaded. The BMP uses 1.375"OD/.50"ID while Staton uses 1.375"OD and .625"ID. The Staton roller seems more heavy duty and there are more sizes available. Staton roller can be installed in the BMP channel with its matching clutch drum. However, the Staton outboard bearing will NOT offer full support. Because the BMP channel is thinner, bearing surface and support is compromised if mounted the way that BOTH vendors normally install the OUTBOARD bearing.

What I've done is reverse-mount the bearing so that the snapring is on the OUTSIDE of the housing. A bearing flangette retainer will then be mounted outboard, resulting in additional bearing support and surface area for Staton roller in BMP housing.

I am SO STOKED!!!