DIY Friction Drive : Lowracer Style

[lowracer]

Since dismantling the pusher trailer I recently built, this new project started out as a center engine mount using the jackshaft & pulleys to power the friction drive roller. I didnt like the jackshaft & felt like it ate up too much power w/ additional friction, so I simply mounted a BMP roller onto a Staton 1/2" double bearing clutch driver unit. There is definitely much less friction running it directly without the added complexity of the pulleys, pillow blocks, jackshaft & mounting hardware, & so far tire wear seems low (no black dust all over the place). I think the Maxxis Hookworm 2.5 is a good tire for friction drives since its so HUGE. The whole mount took me half a day to build & has a nice quick release to the inside for the up & down roller adjustment. I'll leave it like this for a bit. Maybe beef it up with additional supports, maybe install the expansion chamber & a single speed conversion for the cassette & probably a 32T front chainring instead of the 46T on there now...
-Lowracer-

 

[noisydad]

Nice job - less is more.

 

[lowracer]

*** Switched it to V-Belt Drive ***

Well,
I'm back to my old ways again, not wanting to leave well enough alone.
I like friction drive, in fact I took one of my MB's to work yesterday (around 60 miles of riding). This is the one with the Subaru Robin EH035 driving a BMP friction kit. The thing performed flawlessly & got around 135-145 mpg's. Just needs more power to drive thru the wind and to cruise at over 30 mph without being at WOT the whole time.
I didnt much like the DIY friction set-up on this bike with this engine, so I went & converted it to my tried & true v-belt drive. It gets out of its own way in a hurry now & easily cruises at 30 mph at half throttle.
Here are a few pics...enjoy
I'll probably install the expansion chamber after I do some more test drives.
-Lowracer-

 

[lowracer]

I took the bike in its current configuration (v-belt, rear drive, rear mount) for a ride today to make sure its set up correctly & made a few adjustments. This is a sweet set-up & has great acceleration right off the line & pulls strong to an impressive top end.
Hopefully I wont get a wild hair & will leave it like this now for awhile.
I tried to mount the expansion chamber today but wont be able to without modifying it with some flex pipe to clear the frame. I'll stick with the little exhaust can until I get motivated to change it. Performance suffers a little with the small can, but isn't as bad as you would imagine.
I'm still in love with these little high performance Cag engines & although I started busting clutch springs I can't imagine going back to just 1.6hp full time...
I may give this new MB a workout this week by taking it to work one day & putting about 60 miles or so on it. I gotta come up with a name for it too I guess...?
-Lowracer-

 

[rawly old]

Say Low,
A while back someone mentioned a performance carb for a PF-4000, but
I can't quite remember the number. Was it WYK-58 or WYK- 85??

 

[grinningremlin]

Say Low,
A while back someone mentioned a performance carb for a PF-4000, but
I can't quite remember the number. Was it WYK-58 or WYK- 85??

WYK-58.Gotta luv this diy GEBE.Have to see if there's a savings in the drive unit between Staton's and Golden Eagles.May be able to
save a few $$.

 

[rawly old]

Thx Grem, wasn't sure. I keep bouncing back & forth twixt
friction & my diy belt drive. They both have advantages.
I'll go back to the belt as soon as the wet season returns.

 

[lowracer]

rawly,
I dont recall info for a performance carb for the Tanaka 40cc.
I have a Tanaka 47r now & it has a performance carb & is much noisier than my 40cc.
I installed the same mufflers on both & a meter of silicone exhaust hose, but its still just as noisy as before (so its coming from the intake side of things).
I wouldn't change the carb. I get much better fuel economy with the 40cc (150 vs 99 mpg's).
I have gone full circle & no longer use v-belt drive or friction drive on my current machine.
It is a dual engine, all wheel drive, chain drive w/freewheel (no engine braking)...
Clutches should last much longer now (I'd rather replace brake pads than clutch shoes) & no more broken clutch springs.
-lowracer-

 

[rawly old]

That is just freaky lookin'! It can't remotely be street legal?
Low, ya got to much time on yur hands....really.
The reason I asked about the carb is that I have an old HF 52
that I think would work well with that carb, or at least I'd have
a spare for the tanaka.
Something I've discovered to save clutch springs, the holes
they mount to are drilled straight thru & have square edges.
I use a diamond tipped needle bit to round off the edges of
the holes to match the curve of the spring. That way the
edge doesn't cut into the spring.
I get those bits cheap from 'Widget Supply.com' in assortments
of 20. They actually dental bits. You do have a dremel?

 

[rawly old]

Oh say, Grem & Low,
I really like the belt setup above; it's very similar
to mine. One thing I found having used both is that
a 3L fractional hp. belt works better than a v-belt
because it's more flexible. That or a cogged 3L
if you can find the right timing gear pulley.
Also, the more acute an angle from the pulley
to the sheave, the better the pulley grips
Which leads me to the question where'd you
get yur pulley,Low, what size?