First Build, 4-stroke 3.5 hp on a Schwinn Bike

GoldenMotor.com

LS614

Active Member
Dec 22, 2009
1,236
3
36
CT and MA
I think that operation is a little too tricky for what he can do, not to dis you Kristof :) I think if I had a choice I would get a hub wear I could replace the steel balls with the all-ceramic wheel bearings you can get on ebay for pretty cheap. The bearings are EVERYTHING
 

mapbike

Well-Known Member
Mar 14, 2010
5,502
109
63
Central Area of Texas
Anyone have a bike they can give away?
Anyone know where I can get a free bike?
Dont know where you can get a freee bike but I would like to suggest something to you if you dont mind....

I have many years of experience working on and rebuilding small engines, now this doesnt at all mean that I know it all, but I can tell you that the way you have your throttle set up is one of your major lack of RPM's problems because your cable has that huge swag in it and even though it will pull the govenor arm enough to increase throttle as soon as the govenors internal weights in side the engine sling out an force a fairly good amount of pressure on the arm your throttle is being limited, the correct way to bypass the govenor is to remove the engines side cover and then remove either those stel weights that sling out to force throttle back or to remove the nylon gear that runs on the camshaft and gring all the teeth of of it and then reinstall it so it no longer run against the cam gear, this will elinminate the govenor and allow full throttle without restriction.

I have done this on many engines I have built up for fast gocarts or fast mini bike through the years, just be careful over reving a Techumseh Engine, they produce great power because of their Large Bore and Short Stroke compared to a Briggs Engine, but they are also known for putting a con Rod through the block if you over rev them usually do to the Con Rod bolts coming loose, this was a flaw with the Techumseh Engines because of how the Rod Cap fits to the Rod, they dont interlock like the old briggs engines did, they just had a saw tooth pattern machined into each the Rod and cap and they just meshed together, slung a rod through the block on an old HS50 Techumseh 5HP not long after removing the govenor one time.

Sorry about the wheel bearing trouble also, many of the bike wheels now days come from China with a very small amount of grease in the bearings, so it is very wise to always check, clean, and repack the bearing with a tacky high quality grease.

Good luck and I hope you get that raskle back up on the road soon.
 

Kristof

New Member
Jan 21, 2011
232
0
0
Aliso Viejo, CA
Well... I'm back...with good news(I hope.)

So, I emailed a friend if he has a bike he doesnt use. He said he will email me back the same day..., didnt email me back(some friend...). So after 5 days, I emailed and asked are you going to send that picture?

This is what he emailed me:



Now, I see 3 options here.

#1.) I use one of those wheels and put it on the bike that I have built right now.
-But the frame under the engine is not aligned with the bike anymore, due to some people pushing it over(by accident) at my school... =(
-I am not too happy with the bike or the design... it might ruin the wheel hub again... idk.

#2.) I use the bike to make a full suspension 4-stroke?
-For me, this would be building a motorized bike 2.0(full suspension)
-Full suspension sounds too good to be true.(with a bulky 4-stroke)
-I have no idea how to solve the chain tension problem, when the full suspension kicks in...any ideas?
-I see some serious frame modifications in the future...
-More money to put into this insanity...
-Where and how to mount the engine?

#3.) Leave it alone.
-Im leaning towards this... it will cut my losses monetarily, physically, and mentally.

I have no idea what to make of this scenario.
Its hard to describe every little detail, but please help me to decide.
 
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LS614

Active Member
Dec 22, 2009
1,236
3
36
CT and MA
I'm really sorry for all the trouble you had with your build. I don't want to tell you to give up, but I think that you should cut your losses and sell the engine on craigslist. Save up money here and there in a BIKE FUND jar and keep your eyes peeled on ebay and craigslist for a robin subaru eho35 engine. Once you have that engine, or a small two stroke engine with a 54mm clutch, (cheaper but less reliable than the robin subaru, could find at a tagsale though) talk to us about friction drive! Peace :)
-LS
 

Kristof

New Member
Jan 21, 2011
232
0
0
Aliso Viejo, CA
The bike that my friend offered is way too small. The tires are too small for my current bike as well. So Im stuck again.

Im not paying $40-50 dollars for a new wheel...
who knows maybe the engine rack might have screwed the wheel hub, because of the weight or torque or who knows...
 

LS614

Active Member
Dec 22, 2009
1,236
3
36
CT and MA
Yeah you gotta love the CT dumps, they're just little local places the govt. doesn't touch (I figure CA it's different) You go in, shout at an old fat dude or short dude with hearing issues who's listening to opera in his plywood shack, and pick whatever you want! The dump has made me more than $100! :D
 

4950cycle

New Member
Sep 8, 2010
111
1
0
Dunnellon,FL.
IMHO it looks to heavily built. It is not a battle ship, It is a motor bike. Good construction though. My first 8 inch friction wheel build was very simular to this. While fun & fast it was "WAY" clumbsy while off the bike with all that gantry crane out back