BIKEMOTORPARTS.COM...Anyone Using?

[Porkchop]

O.K. I did a search and found a GP460. Looks and sounds like an awsome machine, and you're going to mount it on a friction drive kit from Bikemotorparts ? Is that not to much power and/or torque for most stock, store bicycles. Let alone how many tires, brakes and clutches you could run through in a week's time. I have the engine from Harbour Freight's auger that's mentioned on Bikemotorparts site. I've had it over a year and it's never had a drop of gasoline put in it. Still in the box ! I've got the Grubee 50 on the way. Still haven't decided which one I'm going to do first. but will probably end up doing one of each ! And I do remember seeing in my dream catalogs when I was probably pre-teens, somewhere like popular Mchanics, pretty much the same friction drive set up as what's on today's market. It had a tension spring that pulled the drive bar, or whatever you call it, down onto the wheel, and it had a handlebar lever you pulled to raise the drive bar up off the tire. I imagine you could use one of the clutch levers with the locking pin to do that. Would probably have to get a very strong tension spring and rig up a cam system on the lever kind of like a compound hunting bow to take a lot of the tension off your grip. Pull the lever, lock it in place to keep the friction off the tire, and there you go ! Of course you'd have to figure out a way to make a pivot point for the motor. And then again, the way there system is made it should already have one ! Personally, I think it would be an easy thing to do. I wish I was a machinist. I know my buddy is going to get tired of me and my project unless there's a way I can make him money off of it ! Anyway, that GP460 sounds like a funeral waiting to happen for someone that does not respet power and speed.

 

[5-7HEAVEN]

Porkchop, friction drives and centrifugal clutches are your friend. There are no chains to break, whip or fall into the spokes. Because of the low gearing due to the tiny roller (1.25") and large 26" wheel, proper gearing to match the engine's potential is possible.

Centrifugal clutches with 3,000rpm springs will tame the mightiest engine. I've eaten several tires due to improper pressure between roller and tire. I have used several engines and have NEVER fried a clutch. I might've changed brake pads once.

"The Dragon Lady" has twin 2.2hp 43cc Mitsubishi engines with ADA S1 expansion pipes. Braking is handled by front vee, rear side-pull calipers, coaster brake and massive resistance drag from twin friction drives. The girlie cruiser brakes reliably and often from 35-38mph speeds.

I have respect AND control over speed and power.

To replace both engines with a 5hp single motor might be an even swap in horsepower and a probable loss in torque. The GP460 engine's torque starts near 8000rpm, whereas the Mitsubishis make their power at a much lower rpm.

To install a GP460 rear engine w/friction drive seems sensible.

To place a SECOND 460 engine up front would be crazy.

I LIKE crazy. As long as I can control the power, all is good.

Twin engines are great. When one engine conks out, the other drives you home.(happened several times).

ANNND projected top speed is a manageable 40mph.

 

[5-7HEAVEN]

Engagement Lever

Porkchop, I fabricated an engage/disengage lever for the front engine when I first installed twin motors. I did it so that I could lift the front drive off the tire. The front roller was 1.25" or 1.375". That engine would produce more low end and peak early. When it did, the idea was to lift the front roller to disengage the motor and eliminate the spindle's resistive drag from the front tire. The rear engine alone would be called upon to maintain top speed.

It cost less than $20 to fab the lever. I used simple components like .50" box tubing for the 24" lever, a pivot from a roller caster, a solid roller caster to press down upon the drive housing and springs to lift the roller/housing off the tire. The struts were disconnected from the housing and served as an archway to attach the springs and pivot for the lever.

The lever worked very well but its arc was right down the middle of my front basket. When I installed the front suspension fork, the struts' attachment angles were incorrect to properly reinstall the archway. I needed the basket more than the lever, so the basket stayed.

Now that both engines have 1.5" rollers, there's no need to engage/disengage the engine. Five hp is pushing the bike at top speed, which is twice what would have been available with the disengagement theory. It just takes a few seconds longer to reach maximum because of the larger friction rollers.

Although the throttles don't need to be synchronized, both motors sing in harmony at any and all speeds.

BTW, I picked up most of the components of a vintage Dimension Edge kit, probably 20 years old. The housing is a flimsy .125" sheet aluminum, not like the current DE's .25" extruded aluminum housing. The bolt pattern was for smaller 54mm clutches. I'll probably not use the housing, but its engagement assembly might adapt to a BMP or Staton friction drive assembly.

 

[Rich 240]

BMP Friction Drive

yes. I bought one based on my folding bike needs. They don't sell engines so I went elsewhere for my Honda engine. It's the only friction drive I have built so bear that in mind. Other than having to shorten the rear stays because of the small wheel diameter, it went together quick and easy. My frame is chrome molly, the strongest frame Dahon makes (according to their sales information). I cannot speak to tire wear as I just finished the kit this past week, but I am thrilled with with the operation of the friction drive. As far as freewheeling, I have accidently left the friction drive in the "on" position several times and really didn't notice a big difference in pedaling effort, it's pretty much the same, not like a china girl with the heavy chain and sprocket that I had before.
As far as the engine hanging out over the side, I too found this sort of objectionable and though about mounting it on top of the rack but rejected the idea after installing because it just runs so darn good the way it is and anything else would just add more complexity to what is a very simple design.
Stanton, dimension edge and bmp all use essentially the same method for mounting engines and probably would have come up with another method, maybe even tried the top mounting. Apparently they all find that this system uses the fewest number of moving parts and provides the highest
possible degree of dependability otherwise I would suspect kits would have been configured differently over the years.
This is truly a "direct drive" system with no "links" in the chain to break.
As such, the form follows the function, sort of like the old volkswagens, so the engine, being offset as it is, is something I am quickly getting used to. By understanding "why" it is how it is I can appreciate its simplicity and not try to "reinvent" it. Two things I have learned over the years are "if it aint broke, don't fix it" and "don't mess with success".
The Dimension Edge would appear to get a premium for it's unique lever actuation mechanism and the extra convenience, ease of use is definitely something to consider.
The other thing about any of these is they can be easily moved from one bike to another in minutes.
The only down sides are the need to use a relatively smooth tire and possibly poor wet weather performance. My plans don't involve riding my bike in wet weather so a friction drive is just right for my needs.
There are pix of my bike in the gallery to see what it looks like installed.

 

[vegaspaddy]

thats a nice setup rich, i imagine coming form a CG this is night and day,

the friction setups are by far the least complicated and easiest way to motorize your bike, i have a staton bought from another member with the mits engine, and i also have a De kit on my wifes trike with the easy enagage, disengage, i can see way you pay the extra cash but for the money the basic friction kit can not be beat.

http://www.motoredbikes.com/showthread.php?t=16164
http://www.motoredbikes.com/showthread.php?t=9468

 

[5-7HEAVEN]

The BMP Kit Is Here!

Guys, the kit arrived yesterday. I was tired from work and a 15-mile trial ride from work to night school. (Can't get over it; it takes minimum 54 minutes to drive 10.5 miles in rush hour and 37 minutes by MB!)

Opened the kit at 4am. Postage was free which cost the vendor $13.50. I would've paid $56 shipping from another vendor.

Whomever packed the kit did an EXCELLENT job. I was impressed; one of the best packed box I've ever received. Lots of paper stuffing and the engine channel was wrapped separately in thin styrofoam sheet. Everything painted nice and neat, little stuff all bagged individually.

What I liked best was that the engine channel was machined to SLIP-FIT!!! the bearings! Yes! The shaft that holds the bearings is a pressfit with locking collars and roller with one-way bearing.

I didn't like the way the driveshaft protrudes into the clutch area. Unsure if it would contact the engine's clutch...so I decided to use Staton's roller, clutch drum and spacer with this BMP friction drive. That way I have more spindle options. BMP has 1", 1.25" and urethane 1.5" rollers. Staton has .875", 1", 1.125", 1.25", 1.375" and 1.5" rollers. Yes, differences in size does matter for engine performance.

BMP clutch drum and driveshaft have metric threads, whereas Staton is American. Not interchangeable for parts.

Staton uses a circular 1.25" engine spacer; BMP uses .875" long aluminum tubes as engine spacers. Staton's spacer is much stronger, but BMP's allows the clutch drum to travel .375" deeper for more clutch contact. According to the wear on the used clutch drum, Staton has .5625" clutch depth while BMP should have .875" depth.

That's a 56% difference in clutch surface!

Staton's clutch area could be improved by machining its clutch spacer.

Since BMP's driveshaft is .5" diameter, they use different-size ID bearings than Staton. The bearings I bought on ebay don't use snap rings. I'll need to get the ones w/snap rings especially since they're a slip-fit in the engine channel.

There is only one hole to position the rear struts on the engine channel. Unsure if that's gonna be a problem for me.

more to follow.

 

[Happy Valley]

I have FDs from Staton, DE and BMP. The BMP is from last year when they were still using the 1/4" aluminum channel, like the other two.

All three of these seemed about equally rugged other than one thing about the BMP U-bracket which was a bit flimsy. 1" strapping compared to the much more rigid 1 1/4". It made getting the engine/drive/spindle assembly 90 degrees to the wheel plane more problematic until I swapped it for the heavier Staton.

Now I see the BMP has changed out from the rigid 1/4' extruded aluminum channel to bent sheet steel. I asked the guys there if they had anymore of the aluminum channels, was told no, these are just as good and they only weigh a pound more.

So just how much flex is in the sheet steel channel?

 

[5-7HEAVEN]

Happy, the engine channel is .125" steel PLATE. It is rigid and I believe as strong as the extruded aluminum.

I acquired a very old Dimension Edge kit. THAT engine channel is .125" ALUMINUM plate, which is weaker and more flexy than this BMP engine channel.

I do not anticipate any problems with this steel plate.

I AM having problems mounting the Staton clutch drum spacer. It is a fraction of an inch too wide and won't allow the four bolts to thread into the engine block.

It could be because the engine bolt circle is metric and the clutch drum spacer is American measurement.

Maybe that's way this kit has aluminum tubes for spacers instead of the other vendor'sdrum spacer. Tubes are also cheaper to make.

 

[Rich 240]

The BMP U bracket seem to work fine on my Dahon folder. I have shorten the rear stays because of the smaller wheel diameter so maybe that helped as far as creating a more compact package with a bit less flex. I could see where the u bracket could "torque" a little on longer rear rear stays.
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.

As far as the steel vs. aluminum, I'll take the bent steel over the aluminum because I think the steel will probably stand up to the stress and strain applied to it in this application.

Stanton's design and install is somewhat different than BMP and DE is a little different still so I believe each designer of the respective FD setups has executed a unique and functional design not necessarily superior or inferior to the others, just different.

This give us a better selection to choose from and flexibility select a kit that best fits the bike we are installing it on.

I also appreciate the care attention with which my BMP kit was boxed up.

There was one part I had to ad lib and that was the cable adjuster for the throttle that fits on the engine. My BMP kit did not include it nor did it come with the engine I purchased from the engine supplier I used.

I can't really fault BMP because they would have no way of knowing what engine I was using the throttle cable on. Nor can I really fault the engine supplier because they could just as easily assume it would be part of the throttle cable, I suppose.

I purchased a cable adjuster like that on a bicycle handbrake lever and installed it with two jam nuts one on either side of the molded mount on the engine. It seems to be working fine. I would prefer to have the brass cable adjuster I have seen in various installation instructions but I don't know where I might find this part, if anyone knows please advise. Thanks.

Also, when I first started my engine, it idled at a fairly high rpm. I don't like high idles, so I started looking into how I could possibly lower it. Honda's CX35 engine has a small phillips head screw on the throttle assembly that will adjust this. I backed the screw out a bit and the idle dropped to a much more comfortable level.

 

[Porkchop]

Guys, the kit arrived yesterday. I was tired from work and a 15-mile trial ride from work to night school. (Can't get over it; it takes minimum 54 minutes to drive 10.5 miles in rush hour and 37 minutes by MB!)

Opened the kit at 4am. Postage was free which cost the vendor $13.50. I would've paid $56 shipping from another vendor.

Whomever packed the kit did an EXCELLENT job. I was impressed; one of the best packed box I've ever received. Lots of paper stuffing and the engine channel was wrapped separately in thin styrofoam sheet. Everything painted nice and neat, little stuff all bagged individually.

What I liked best was that the engine channel was machined to SLIP-FIT!!! the bearings! Yes! The shaft that holds the bearings is a pressfit with locking collars and roller with one-way bearing.

I didn't like the way the driveshaft protrudes into the clutch area. Unsure if it would contact the engine's clutch...so I decided to use Staton's roller, clutch drum and spacer with this BMP friction drive. That way I have more spindle options. BMP has 1", 1.25" and urethane 1.5" rollers. Staton has .875", 1", 1.125", 1.25", 1.375" and 1.5" rollers. Yes, differences in size does matter for engine performance.

BMP clutch drum and driveshaft have metric threads, whereas Staton is American. Not interchangeable for parts.

Staton uses a circular 1.25" engine spacer; BMP uses .875" long aluminum tubes as engine spacers. Staton's spacer is much stronger, but BMP's allows the clutch drum to travel .375" deeper for more clutch contact. According to the wear on the used clutch drum, Staton has .5625" clutch depth while BMP should have .875" depth.

That's a 56% difference in clutch surface!

Staton's clutch area could be improved by machining its clutch spacer.

Since BMP's driveshaft is .5" diameter, they use different-size ID bearings than Staton. The bearings I bought on ebay don't use snap rings. I'll need to get the ones w/snap rings especially since they're a slip-fit in the engine channel.

There is only one hole to position the rear struts on the engine channel. Unsure if that's gonna be a problem for me.

more to follow.

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 !