Schwinn High Timber hi speed build

Just burn regular gas and go to 32:1 mix. You are running to much oil..

These are my recommendations

Get a 36T rear sprocket. I can run 35 mph with mine. 30-33 is easy cruise.

You're running too much oil. 28:1 is good enough for break in. After that follow the oil manufacturers recommendation, or at least 32:1. Most synthetics run about 40:1 or higher.

Rejet you carb. Assuming you have an NT, try a 68, or 66, with the needle clip in the second from top position.

Try a NGK BP6HS spark plug. In winter you can run BP5HS.

That should get you to 35 mph.

My Flying Horse 80 motor is basically stock, but it has a Speed carb, with shorty intake manifold. A modified exhaust, but still as quiet as a stock muffler. Nothing done inside the motor. For the record I weigh 230, and my bike weighs 57 lb

graydog8josh said:

here are pictures of my jb weld job on the carb.

Does anyone have any hard data on how much opening up the intake tube from stock improves top speed or torque or hp or anything?

I think i might take the dremel to it.

Click to expand...

graydog8josh said:

"Get a 36T rear sprocket. I can run 35 mph with mine. 30-33 is easy cruise."

who makes the best 36t? is kings the best. Are the aluminum sprockets pretty high quality? I just bought the 41t from dax because i thought that would be the most the motor could handle.

"You're running too much oil. 28:1 is good enough for break in. After that follow the oil manufacturers recommendation, or at least 32:1. Most synthetics run about 40:1 or higher."

My new tank of gas is 32:1, so maybe ill see something change


"Rejet you carb. Assuming you have an NT, try a 68, or 66, with the needle clip in the second from top position."

Ive got a 66 from SBP in the mail. when i rejet it will change my needle position? I definitely cant get it to run smoothly on any position but the center right now.

Click to expand...

First off, you need to junk that manifold. That's costing you half your power. Measure and see if a shorty will fit. All you need is 4 1/2" from your cylinder flange to the seat post tube. If that won't work you'll need to buy an offset manifold.

I assume you're using a rag joint for your rear sprocket. Check with kings and ask it they have sprockets that are compatible with a stock rag joint. Be sure and let them know how many bolt holes you have. Their sprockets are very high quality, and will last a long time.

It's ok to make your own intake gaskets. You can buy gasket material at a auto supply. I would try changing the needle right away since it doesn't cost anything, and you don't need any parts to do it, but I wouldn't expect much with your crappy intake. I'm running a 66 jet in my bike, and it will probably work for you, but keep an eye on your spark plug at first to make sure it's not too lean.

With a 36T you will be able to pull up a moderate hill, but steep long hills may need pedal assist.

This is what a 40T sprocket would do for you. I have this gearing at one time and I could cruise easily at 26-30, and top out about 33-34. More than that was screaming the motor.

RPM MPH

1000 4.7
1200 5.7
1400 6.6
1600 7.6
1800 8.5
2000 9.4
2200 10.4
2400 11.3
2600 12.3
2800 13.2
3000 14.2
3200 15.1
3400 16.1
3600 17.0
3800 17.9
4000 18.9
4200 19.8
4400 20.8
4600 21.7
4800 22.7
5000 23.6
5200 24.6
5400 25.5
5600 26.5
5800 27.4
6000 28.3
6200 29.3
6400 30.2
6600 31.2
6800 32.1
7000 33.1

This is what a 36T will do. This is what I have now. I can cruise 33-35, and top out about 38.


RPM MPH
1000 5.2
1200 6.2
1400 7.2
1600 8.3
1800 9.3
2000 10.3
2200 11.4
2400 12.4
2600 13.4
2800 14.5
3000 15.5
3200 16.5
3400 17.6
3600 18.6
3800 19.6
4000 20.7
4200 21.7
4400 22.7
4600 23.8
4800 24.8
5000 25.8
5200 26.9
5400 27.9
5600 28.9
5800 30.0
6000 31.0
6200 32.0
6400 33.1
6600 34.1
6800 35.1
7000 36.2

graydog8josh said:

one more thing. I stumbled upon this while researching the jaguar cdi. My instruction manual with the first motor says to hook the kill switch up to the white wire and to ground, while everything else in the world says that is an auxillary low voltage for lighting. What is that doing? It kills the motor so it works, but i dont think its doing it the way its supposed to. Can someone explain this phenomenon to me in detail?

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Hooking the kill to the white, or blue wire has about the same result. It shorts the magneto windings together. We're talking dead short. This isn't a very good way to kill the motor, but it's a pretty good way to kill the magneto coil lol. I assume the reason for recommending the white wire over the blue one is because it may subject the coil windings to less current when you hit the kill button.

When the motor is running, the magneto coil makes heat. Hot weather will make it even warmer. When you hit the kill button, it shorts the magneto winding, which takes power away from the CDI killing the motor. The problem is that as long as the motor is turning, the coil makes some power. Before the motor stops completely it momentarily subjects the magneto coil windings to high current. There's danger the coil windings burn up. It's probably not as much a concern in cooler climes.

SBP sells a kill switch which is a rocker switch. It allows you to wire the kill differently, where you can open the circuit to the CDI instead of shorting the windings together. It's a good option to consider if you live in a hot clime.

The clutch gear has a big bearing that has something like 40 to 50 balls in it. You can squeeze grease into the crack on the gear with your finger.

A better way to grease that bearing is to remove the clutch gear off the transmission shaft. On the back side are 3 holes. You can use a grease gun to inject grease into the 3 holes.

That will go a long way making the clutch quieter. Some of them are just noisy though.

Looks like you're getting there now. Good job.