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Discussion Starter #1
Anyone ever built a set of electric starter rollers?

I'm halfway through a set, using two honda starter motors. With rollers 2.5" in diameter about 8" wide, knurled in the center 4". I plan to space the rollers about 8" apart with about 1/4" or so of adjustment to adjust the chain that connects them. Each roller is driven by it's own motor...but since a bike likes to climb onto one roller sometimes, I'm chaining them together so that there is always power from both motors.
Anybody have any suggestions for spacing the rollers...8" is just a guess...seems to give enough for the tire to drop between.

As to why rollers for my little bikes....it's hard to push start them in my shop in the middle of winter.
JohnnyB
 

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Kevin Campbell built some nice rollers last year based loosly on the Doc Z rollers. He did an outstanding job.
John, your dims seem pretty reasonable based on my memory of my rollers (Doc-Z). Scooter wheels with abec 5 bearings centered on the sides of the rollerskeep the real wheel from crabbing and frictional losses to a minumum.
Great for trouble shooting engine problems and restricted spaces.
 

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Discussion Starter #3
For centering I was going to weld on "funnels" about 3" or so apart on the rollers....picture a very large opening, short funnel, turned sideways and slide over the rollers with the big ends facing out. The tire shouldn't want to climb these funnels...and even if it tries to they are welded to the rollers so they are turning also.

Rather than welding much of the whole unit I'm machining and bolting pieces together to allow for design changes, easy motor changes, spacing, roller type etc.
JohnnyB
 

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Discussion Starter #5
I freakin knew you were going to say that. Problem is....I have serious doubts as to if these would start anything larger than a 175. I know Turk uses them for his Bulto...but that's a two stroke.
We'll have to give it a shot sometime if it starts the 175 easy...I've got plenty of spare motors if I burn one out :)

JohnnyB
 

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JB my rollers with the gas engine are 3 inch and are 14 inches center to center. Are yours just bare metal or rubber covered? I think they might have to have rubber to work, not jsut knurled. But what do I know. The rollers that Aron has are steel as I remember but they have "webbed" cut outs, if you get what I mean.
 

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Yeah, our "team" has the Doc Z set-up with a starter motor for each roller and the lightened, grip slotted rollers. Can't start the Duc without 'em. You can get the rollers by themselves from Doc Z...
 

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quote: am kidding.... really if i am not fit enough to bump my honda... i shouldn't be racin
monkey,

I shouldn't be racin'. i cant start my 250 ducati with out rollers.
 

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JB,
Turk's starter has worked fine on a CB350 that was reluctant to start. Just saying. In case I ever stay in the infield with you field people.
Craig
 

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buckys car rollers used to be knurled, but now they are smooth. like smooth dowels. it starts his bmw no prob.

jc
 

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Discussion Starter #12
Evil,
Yeah I've seen the "web" cut outs. Mine are nicely knurled steel, might be enough with a 175. Hmmm 14"...I might move mine out farther than 8" then. I know the farther the spacing the less "knurl" you need cause the tire wedges in more. Maybe I can find some big radiator hose or something I can press over the knurled section with some glue.
Are your rollers for your 500? That's a tall order compared to a 175.

Craig,
If Turk's has worked on a 350 then mine should work for a 175....seems like his might have 3 motors on it...but I know the one I saw him using had Honda starter motors on it.
After I worked out all the ratios it should technically have more balls than a stock engine mounted starter.
JohnnyB
 

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branson
screw the funnels. if you can't ride your rig a bit crossed up on rollers, what the heck you gonna do when you start riding like a man on the track?
-parks
 

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I've been thinking about building a set. A friend gave me a pair of rollers ( probably about 2" dia.) and the motor from a treadmill. I have to figure out 1; how to control the motor 2; how to get the rollers to have enough grip for the tire but not so much that if it doesn't start the rollers dig cylinders into the rubber.
I figured I'd do chain drive from the motor to the driven roller instead of belt, I suppose I could drive both rollers...
I still don't know if it would start my 500 single, that baby is kinda picky when it comes to that, but I suspect it would work for a twin.

FR
 

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I've got Kevins rollers here right now, and he did a really nice job. The drums were originally a roller from a commercial mower they have at the golf course he cut in half and welded end caps on. The motor is some electric motor/generater thing from a golf cart that was flooded and he rebuilt. I know it'll spin his 450.
 

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Discussion Starter #16
I think you'd have a hard time starting a 500 single with 2" rollers. I made my rollers out of sections of pipe that I welded end caps on and trued up on a lathe.

I made a giant, vehicle driven 5" diameter set for Fritz Augustine to start his Guzzi and his Cagiva 500 factor GP machine.

Not sure if a treadmill motor would work. I know a lot of guys use them for variable speed drives on lathes...but they don't have a lot of starting torque and you'd need a real hefty controller for the amount of juice you'd have to pump to one. For larger bikes I've seen numerous people use V8 starter motors.

Honda starter motors actually have a planetary gear set in them I think. The actual output shaft turns slower than the rotor in the motor.

JohnnyB
 

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and another thing...why knurls...didn't think you were doing the rain anymore.
-parks
ps no offense to jersey girl who rides beautifully without being a man.
 

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PS. The rollers on my set are from a commercial conveyor company. They make all kinds of rollers, with bearings, and you just have to specify width and diameter. Conveyor companies are your friends for a lOT of different reasons. Look up in the book for the one nearest you.
 

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my sup vint honda is not so bad to start.... as long as i am not a sidecar monkey... i should be fine. dude when you are totally toasted from being a monkey and the temp is 80 degrees plus... it is a total pain in the arse to bump start anything.

this season should be mellow
 
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