friction roller dai/speed

zukjay

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Jan 9, 2009
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here are some numbers i crunched to come up with some general top speeds for different sized roller. of course this asumes you engine has the umph to turn at 6000rpm while loaded and also factor in some loss of energy to friction and wind. this should help some folks out. tire size doesnt matter much with friction drive, except a taller tire traverses variances(pot holes, curbs, debris) in the road much easier than a small say 12"-16" wheel. but thats not to say small wheels wont work just that there not ideal.


mph at 6000rpm

roller dia. Speed

1" 17mph
1 1/4" 22mph
1 1/2" 26mph
1 5/8" 29mph
1 3/4" 31mph
 
mph at 6000rpm

roller dia. Speed

1" 17mph
1 1/4" 22mph
1 1/2" 26mph
1 5/8" 29mph
1 3/4" 31mph

seems to be off just a little

1" roller with a 1.6 hp hits around 22.5 mph with a 200 lb rider

note -- a 1 3/4" roller is a pretty large THING
think that your miles per hour would be higher (38 mph ?) -- if it could be done
may not have the top end -- so as to get there

always fun as we ride those friction driven THINGS
 
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His figures are correct for 6000 rpm

HP has nothing to do with the calculation except if you
don't have enough HP to pull your ratio

Same goes for your weight

Your Robin Subaru 35 cc motor pulls higher than 6000 rpm
Probably redlines at 7600 rpm like the Honda gx 35

I just bought a Staton Robin Subaru friction drive with a 1 1/8" roller,
just got it yesterday so I haven't installed it yet

At 6000 rpm it will pull 20.1 mph
7600 rpm = 25.4 mph

Is your clutch drum still ringing and dinging MM?

seems to be off just a little

1" roller with a 1.6 hp hits around 22.5 mph with a 200 lb rider

note -- a 1 3/4" roller is a pretty large THING
think that your miles per hour would be higher (38 mph ?) -- if it could be done
may not have the top end -- so as to get there

always fun as we ride those friction driven THINGS
 
At 6000 rpm it will pull 20.1 mph
7600 rpm = 25.4 mph
Is your clutch drum still ringing and dinging MM?

that would be a nice top speed Forbisher 25.4
after being broken in -- would like to know if you reach that
mine seems pretty peaked out at 22.5 mph with the 1" roller

my clutch drum
think that it's making typical centrifugal clutch sounds
guess that I am getting used to it also
don't notice it that often
sometimes it seems to do it more than others
runs well though

as I ride that motor bike Thing
 
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What oil are you using in your Robin? 30 weight?

1" roller at 7600 rpm = 22.6 mph so I guess you are
maxing it out
1 1/8" roller at 7600 = 25.4 mph

Should be able to max it out as its pretty flat around here and
I weigh 175 lbs

1 1/4" roller at 7600 = 28.3 mph

I bought my Staton friction drive used so it is already broken in....

I got a spare 7/8" roller and a clutch drum too which I have been
playing with.....
I think I have the clutch ringing problem fixed, just have to test my
modification out on the bike


PS: If DetonatorTuning is reading this....

1 1/2" roller at 10,000 rpm = 44.6 mph
1 1/2" roller at 12,000 rpm = 53.5 mph

that would be a nice top speed Forbisher 25.4
after being broken in -- would like to know if you reach that
mine seems pretty peaked out at 22.5 mph with the 1" roller

my clutch drum
think that it making typical centrifugal clutch sounds
guess that I am getting used to it also
don't notice it that often
sometimes it seems to do it more than others
runs well though
 
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What oil are you using in your Robin? 30 weight?
1" roller at 7600 rpm = 22.6 mph so I guess you are
maxing it out

yes -- using good old 30 weight -- I think that's what was recommended
get's a little hot down here (so calif) in the summers as you know

some have claimed much higher top speed than what I am getting
with the same basic set up

Robin 1.6 hp
1" roller
fair quality mountain bike
overall weight bike and rider 150 aprox
achieving a 22.5 mph on the true level ground

that's almost 1/5 th the speed that my stock Harley's used to do
more than happy with that

all that I can truly say for sure is
anytime on two wheels
it is fun to ride that MB THING
 
yea i went with 6000rpm so im not taxing the engine so much and i dont want to max out at the speed i want to go. here in indiana top speed by law must be 25mph or less(unless no one is look'n) and thats not quite the speed of sound but these things are made for fun anyway right(ive never seen anyone on one without a huge smile) and of course transportation.

are we aloud to ride these on bike trails, by law in Indiana they are not motor vehicles so all the signs that say no motor vehicles shouldn't apply right. but even if the laws doesnt forbid it im sure its would be frowned upon and maybe some harassment by bored policemen. we have so many trails here i could almost go any where in town and barley touch a road its been a few years sense i rode a motorized bike but from what i remember folks on the road just dont care enough to watch out.
 
it seems to me that load(weight) is less of a speed robber than wind well unless on hilly terrain, lower=not slower i bet recumbents are a little faster with any given engine compered to a standard bike
 
hilly terrain

hilly terrain

yes -- the old hilly terrain
will knock off a few mph

regarding riding on bicycle, walking and hiking trails

here in Calif the trails are a no no for sure ticket
but in your state -- never know until you ask

for other questions regarding state MB laws in Calif
I have found law enforcement agencies within the state
e-mailed them my question
I liked their reply
carry a copy with me everywhere I ride my MB

as I ride that THING
 
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