bairdco, i was looking at your pics, great bike by the way, i noticed there is no chain tensioner on engine side. i'am i correct? if so do you have any issues? i really hate the idea of using a chain tensioner but didn't know if i could get away with it. my monark is about the same dimensions as your colson. let me know your findings-big mike
The Backwards Engine Experiment, 1939 Colson
- Thread starter bairdco
- Start date
no issues whatsoever. it's a million times smoother, i've never had the chain jump off, bind up, nothing.
this is the third bike i've built without it. as long as you've got a straight shot, there's no reason to use it.
i spend a lot of time getting everything to line up, and it pays off. the only minor inconvenience is after a week or so, when the sprockets wear in and the chain "stretches," you have re-adjust everything, which basically means moving the wheel back and messing with the pedal side. sometimes there's not enough room to just add a link, so you might have to change out sprockets, or add a link to the motor side, etc... if you notice, my rear wheel is as far forward as possible, because i anticipated having to move it back. which i need to do now that everything's broken in.
it's totally worth it, though. other people will give you all kinds of reasoning why you should run it, but the chain tensioner, isn't. isn't a "tensioner." it's just a guide. a tensioner would be spring loaded. so the whole "it's gonna jump off as the chain slackens and tightens" argument is just nonsense. if you don't need it, trash it.
(please, everyone else. don't argue with me about it here. there's ten other threads where i stated my opinion of it, and i'm tired of it. this isn't the "backwards engine without a chaintensioner please heckle me with your biased opinions without ever having tried it" thread.)
this is the third bike i've built without it. as long as you've got a straight shot, there's no reason to use it.
i spend a lot of time getting everything to line up, and it pays off. the only minor inconvenience is after a week or so, when the sprockets wear in and the chain "stretches," you have re-adjust everything, which basically means moving the wheel back and messing with the pedal side. sometimes there's not enough room to just add a link, so you might have to change out sprockets, or add a link to the motor side, etc... if you notice, my rear wheel is as far forward as possible, because i anticipated having to move it back. which i need to do now that everything's broken in.
it's totally worth it, though. other people will give you all kinds of reasoning why you should run it, but the chain tensioner, isn't. isn't a "tensioner." it's just a guide. a tensioner would be spring loaded. so the whole "it's gonna jump off as the chain slackens and tightens" argument is just nonsense. if you don't need it, trash it.
(please, everyone else. don't argue with me about it here. there's ten other threads where i stated my opinion of it, and i'm tired of it. this isn't the "backwards engine without a chaintensioner please heckle me with your biased opinions without ever having tried it" thread.)
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was out today mingling with traffic. exhaust seems quieter, and it's not as leg warming with the aluminum pipe on it. tried to get video again, but for some reason, my camera shuts off after 30 seconds or so. i thought i had some really cool near misses and speedbump-jumps, but all i got is taking off from lights. wow.
one problem with the backwards set-up is starting. it really takes a lot of pedaling to get it fired up most of the time. i noticed something weird, that i can't explain (yet.)
if you take a normal set-up bike and slowly push it forward, (no clutch) you'll just skid the rear tire from the compression. it takes a shove to get it to through a stroke.
now, if you push the same bike backwards really slow, the wheel will move. you can hear the air getting squished by the piston.
so, mine's opposite. push it forward, and it moves the wheel. backwards, it locks up.
could be that the exhaust port is higher than the intake port. whatever the cause, like i said in an earlier post, you have to jam through a pedal stroke to fire it.
if anyone knows the cause, feel free to enlighten me. and no, it's not a leaking head gasket. there's still loads of compression.
another fun thing today, after going about 25 miles, in traffic at 40+mph, i decided to pull onto the bike trail and try to figure out my video set-up. was doing about 35 when one of the three bolts on my sprocket adapter loosened up and jammed into my coaster brake arm, sending me into a 50' skid.
handled it fine, but if i was in traffic, who knows...
took the bolt out, and limped it home on two. stopped at Macfadden-Dale hardware on the way, got me another button head, and fixed it. dunno why it came loose. maybe it was all the speedbump jump x-ups...
another thing, is i'm done with vintage analog speedometers. burnt up a NOS cadet that cost me $30, and another old stewart warner i got for $5 at the swap meet. i don't think they were made to go 50mph, even though they're numbered that high. if i can make them work again, i'll put them on pedalers.
i think that's it. when it starts raining, i'm gonna work on sound deadening and exhaust manifolds...
one problem with the backwards set-up is starting. it really takes a lot of pedaling to get it fired up most of the time. i noticed something weird, that i can't explain (yet.)
if you take a normal set-up bike and slowly push it forward, (no clutch) you'll just skid the rear tire from the compression. it takes a shove to get it to through a stroke.
now, if you push the same bike backwards really slow, the wheel will move. you can hear the air getting squished by the piston.
so, mine's opposite. push it forward, and it moves the wheel. backwards, it locks up.
could be that the exhaust port is higher than the intake port. whatever the cause, like i said in an earlier post, you have to jam through a pedal stroke to fire it.
if anyone knows the cause, feel free to enlighten me. and no, it's not a leaking head gasket. there's still loads of compression.
another fun thing today, after going about 25 miles, in traffic at 40+mph, i decided to pull onto the bike trail and try to figure out my video set-up. was doing about 35 when one of the three bolts on my sprocket adapter loosened up and jammed into my coaster brake arm, sending me into a 50' skid.
handled it fine, but if i was in traffic, who knows...
took the bolt out, and limped it home on two. stopped at Macfadden-Dale hardware on the way, got me another button head, and fixed it. dunno why it came loose. maybe it was all the speedbump jump x-ups...
another thing, is i'm done with vintage analog speedometers. burnt up a NOS cadet that cost me $30, and another old stewart warner i got for $5 at the swap meet. i don't think they were made to go 50mph, even though they're numbered that high. if i can make them work again, i'll put them on pedalers.
i think that's it. when it starts raining, i'm gonna work on sound deadening and exhaust manifolds...
dunno, don't care. my chain tensioner is a wrench.
wait, you mean on the pedal side? if so, yeah, that would be a good idea.
wait, you mean on the pedal side? if so, yeah, that would be a good idea.
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Check this out... Norman did it first!
http://motorbicycling.com/f13/different-way-mount-tuned-pipe-3170.html
http://motorbicycling.com/f13/different-way-mount-tuned-pipe-3170.html
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RAM AIR! The faster you go the more it's turbo charged...woohoo!
All you need is a velocity stack to replace that stock air filter.
I LIKE it!
yup. that's where i got the idea. i was buggin' him about it for a few weeks, then went for it.
yeah, the only problem is ram rocks. and ram chunks of crap. if i can figure something out that'll let the air in, without sucking up debris, i'll try it out.
dunno if there'll be any noticable effects, but it can't hurt to try. at least then i can prove it to myself.
My airplane has ram air it doesn't really effect it until about 120mph. So if you can get the bicycle up to that speed then you might be able to get the ram air effect.
I was doing some research for you, but I came up empty. I cannot see an obvious reason for the reversal of "feel". I have had dozens of model aircraft glow and diesel engines that would happily run in either direction. I am sure that if you were to alter the ignition timing on any simple(non rotary valved) two stroke, it would run in the opposite direction.
I have quite a few books on the design of two stroke engines, and they didn't shine any light on your problem...but I may have missed something!!
yeah, it's weird. there's no obvious reason for it to have "backwards compression loss" at start-up. i'll figure it out, or deal with it...
so i was trying to figure out my hard starting problem, using the tried and true method of smoking a cigarette and staring at my bike, and i figured that the angle of the intake manifold might have something to do with it.
the carb's perfectly level, but the manifold angles upwards.
when i'm trying to start the bike, the motor will turn, almost to the point of firing, but won't catch right away. it sounds like it's either flooding, or not getting any gas.
so i went with the "no-gas" theory, first, figuring the fuel is trying to go uphill through the manifold.
since i can't ride wheelies down the street to start it, i raised up my floats. it seemed a little low, anyway.
now, the bike fires up right away, nice and easy. hopefully, it'll stay that way, and it's fixed.
on another note, and another problem, the petcock at the gas tank decided to start leaking big time, right when i thought everything was perfect. it's leaking right out of the handle-seal. took it apart, looked fine, put it back together, still leaks.
friggen garbage. i had one off an old moped tank, and now it's just fine. i'm gonna find some good ones and stock up for my next builds. i'm putting those bad pet-cocks down...
the carb's perfectly level, but the manifold angles upwards.
when i'm trying to start the bike, the motor will turn, almost to the point of firing, but won't catch right away. it sounds like it's either flooding, or not getting any gas.
so i went with the "no-gas" theory, first, figuring the fuel is trying to go uphill through the manifold.
since i can't ride wheelies down the street to start it, i raised up my floats. it seemed a little low, anyway.
now, the bike fires up right away, nice and easy. hopefully, it'll stay that way, and it's fixed.
on another note, and another problem, the petcock at the gas tank decided to start leaking big time, right when i thought everything was perfect. it's leaking right out of the handle-seal. took it apart, looked fine, put it back together, still leaks.
friggen garbage. i had one off an old moped tank, and now it's just fine. i'm gonna find some good ones and stock up for my next builds. i'm putting those bad pet-cocks down...
Superb Hot Rodding Award.! someone like" Indian Larry " would approve! he died while riding on his Harley standing on the seat and flying his arms. I once saw a motor he made using different heads to proove it could be done.
I want to get the "motor reversal "and "polish and porting" done to my motor too. and the carb tricks sound super too. the smoothing of operation will be extravigant.... I would enjoy having the tricked motor before I ever start my 1948 Huffy up I have the bike in my room "gas free" for now.
I wonder if the 60 to One ratio you started with would affect start up.
also: Do you plan to thin the mixture as thin as 16 to one?
also" Do you ever work on other people's motors?, and lastly, I vote "You the Winner"of the rustoration Build off since you seem done first. and think you cheated a lil on those workman wheels, did you already have um? or, Do you rely on Bike Karma? it seems once we set our heart to something the Manna from heaven roll in such as your Workman Wheel Eskimo in the Park having some ready to go for ya in the required 24" size. they Rock!
I want to get the "motor reversal "and "polish and porting" done to my motor too. and the carb tricks sound super too. the smoothing of operation will be extravigant.... I would enjoy having the tricked motor before I ever start my 1948 Huffy up I have the bike in my room "gas free" for now.
I wonder if the 60 to One ratio you started with would affect start up.
also: Do you plan to thin the mixture as thin as 16 to one?
also" Do you ever work on other people's motors?, and lastly, I vote "You the Winner"of the rustoration Build off since you seem done first. and think you cheated a lil on those workman wheels, did you already have um? or, Do you rely on Bike Karma? it seems once we set our heart to something the Manna from heaven roll in such as your Workman Wheel Eskimo in the Park having some ready to go for ya in the required 24" size. they Rock!
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first, the 60 to 1 ratio is 60 parts gas to one part oil, or roughly 2 ounces of oil to 1 gallon of gas. this can't be done with regular 2 stroke oil, which calls for, i forget, 7 ounces for break in?
Opti-2 can be run at 100 to 1, which is a little more than an ounce of oil (128oz. in 1 gallon) per gallon.
if you tried this with off the shelf regular oil, you'd destroy your motor.
i ran the bike through a gallon at 60-1, and i'm now running 80-1. it runs great, no smoke, hardly any carbon build up, perfect plug color (needle clip 2nd notch from top,) and smooth all the way through the power band. the motor required virtually no break-in time, and ran great the first time. there's virtually no vibration, even at full RPM. if i could balance a ball bearing somewhere on the bike, like the old Lexus commercials, it would give you an idea of how smooth it is.
i was skeptic at first, thinking no matter how great their claims, the motor would still need more lubrication, but after researching their site, and talking to a rep (they're really helpful and friendly, too,) i've definitely become a believer.
BUT, the motor's only been running for a coupla weeks. dunno how the long-term will play out.
as for the rest of your questions, the wheels were definitely a gift from the bike gods. dunno which side those bike gods are on, good or evil, but it could be that my bike lay abandoned and decaying, dreaming of the day it'd be brought back to life, and sold it's soul in order to be resurrected from the rusted pit it was cast into...
haven't worked on anyone else's motors, or bikes (aside from posting advice on this forum,) and right now, just don't have the time...
...that's not exactly true. i have the time, but not really the desire. i'm too wrapped up in my own projects to take on someone else's.
and thanks for your vote. a vote for Bairdco, is a vote for progress...
Opti-2 can be run at 100 to 1, which is a little more than an ounce of oil (128oz. in 1 gallon) per gallon.
if you tried this with off the shelf regular oil, you'd destroy your motor.
i ran the bike through a gallon at 60-1, and i'm now running 80-1. it runs great, no smoke, hardly any carbon build up, perfect plug color (needle clip 2nd notch from top,) and smooth all the way through the power band. the motor required virtually no break-in time, and ran great the first time. there's virtually no vibration, even at full RPM. if i could balance a ball bearing somewhere on the bike, like the old Lexus commercials, it would give you an idea of how smooth it is.
i was skeptic at first, thinking no matter how great their claims, the motor would still need more lubrication, but after researching their site, and talking to a rep (they're really helpful and friendly, too,) i've definitely become a believer.
BUT, the motor's only been running for a coupla weeks. dunno how the long-term will play out.
as for the rest of your questions, the wheels were definitely a gift from the bike gods. dunno which side those bike gods are on, good or evil, but it could be that my bike lay abandoned and decaying, dreaming of the day it'd be brought back to life, and sold it's soul in order to be resurrected from the rusted pit it was cast into...
haven't worked on anyone else's motors, or bikes (aside from posting advice on this forum,) and right now, just don't have the time...
...that's not exactly true. i have the time, but not really the desire. i'm too wrapped up in my own projects to take on someone else's.
and thanks for your vote. a vote for Bairdco, is a vote for progress...
Really enjoy your threads Baird.
"despite the awesome, head turning, old man annoying, cop noticing, leaf-blowing sound of a nitro-circus back-flipper, it ran really good."
"so i was trying to figure out my hard starting problem, using the tried and true method of smoking a cigarette and staring at my bike, and i figured that the angle of the intake manifold might have something to do with it."
But you have trampled on my patented problem solving method of staring, smoking and scratching my head in bewilderment. You will of course be hearing from my pretend lawyer. (If you can hear her too, means them doctors were nutz)
Really, really cool looking build. Nice job!
"despite the awesome, head turning, old man annoying, cop noticing, leaf-blowing sound of a nitro-circus back-flipper, it ran really good."
"so i was trying to figure out my hard starting problem, using the tried and true method of smoking a cigarette and staring at my bike, and i figured that the angle of the intake manifold might have something to do with it."
But you have trampled on my patented problem solving method of staring, smoking and scratching my head in bewilderment. You will of course be hearing from my pretend lawyer. (If you can hear her too, means them doctors were nutz)
Really, really cool looking build. Nice job!
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thanks dan.
haven't updated this in awhile, because there's no problems with it whatsoever. it's still running strong, with no signs of slowing down. hope it stays that way.
i've changed a few things on the bike, so here's some new pics:
haven't updated this in awhile, because there's no problems with it whatsoever. it's still running strong, with no signs of slowing down. hope it stays that way.
i've changed a few things on the bike, so here's some new pics:
