54 Schwinn 24'' DX My Next Race Bike

[Tony01]

Wowow!!! 8500rpm 4stoke with 4hp... Sounds great. Looks so compact. Must have a really good weigh distribution and looks like it is easy to throw around. Nice chain guards, keep from getting sprayed. Yup you are definitely gonna instill that fear in other racers when ya wind this thing out!

 

[Venice Motor Bikes]

I've been following this build for YEARS!!!

Now I'm finally gonna get to see it in person.

 

[Davezilla]

That's impressive for such a compact engine... I've heard about the mix fuel 4 strokers and it does make sense because it allows for excellent power and torque from a rather small package... I've been following this one ever since I joined this forum and hopefully someday I'll be able to see this bike up close and personal... It looks great, it's definitely unique, and very well built...

 

[msrfan]

Thanks again Dave, it was a big hit and performed well at the race Saturday. I've not yet installed the Hookworms, but the Kiniptions worked pretty good. I have my new flywheel which is a lot heavier and will be testing it shortly. I will post photos as I go.

 

[scotto-]

The bike looked and performed great Dale...it sounded even better! Nice to finally see the bike in person. The very young man riding it seemed confident and raced it quite well. In one of the heat races I passed him in a really bad spot and he handled it very well.

A fantastic build and I think it deserves a really nice paint job now. Good seeing you at the races once again!

 

[msrfan]

Thanks scotto, it took all morning to convince Wyatt that looking back just slowed him down and pulled on the bars and anyone passing would not run into him intentionally. He caught on quickly after that.
His dad, Jeff and I talked to Norm about in frame fuel tanks for the 24'' and a 26'' DX, but haven't decided to go that way yet.
A nice paint job is coming soon, after a few modifications. Nothing like the race track to show the weak points. I used a flexible sleeve and hose clamps to hold the carb flange onto the motor, but when it heated up, it wanted to slip off. So I'm going to have it welded right to the intake tube.
Yes, it was great to see you and your cool bikes again along with all the gang. Also glad to see Gilbert win the final, especially when it looked hopeless between heats. I will try to make the next race.

 

[msrfan]

I got my carb mount welded to the motor. Needs a little clean up and check for pin holes. Then I can assemble it and try it out.

 

[scotto-]

Pinholes will make it run faster....but of course leaner. As long as the aluminum is not melting.....all is well

Looks great Dale!

 

[msrfan]

Yessir scotto. Hate to melt aluminum or burn a valve. I hear AGK can make me a new plastic cam with different timing. May have to look into that. Meanwhile the aluminum key built into the dog bone flywheel is starting to distort due to the weight I added to it. So I have a new flywheel welded onto the adapter on the clutch side that's quite a bit heavier. May not rev as fast but will probably run smoother. Then I can go back to the stock flywheel on the mag side.

 

[msrfan]

The carb fit's better now and is solid.




The flywheel on the right is the stock unit and the other one shows the added weight. It's notched because it was too close to the magnet and interfered with the timing. The extra weight made it spin on the shaft and shear the key out of the taper. We pinned it but found it still wanted to rotate and bend the pin.

 

[msrfan]

Here it is with the stock flywheel back on.




On the left is the adapter we made so the racing clutch would fit the motor and the new flywheel is mounted on a replacement shaft on the right.



It fits nicely with just as little clearance behind.





The test ride went well with some carb and clutch adjusting. Runs smoother and idles nicer. Doesn't rev quite as fast now but the whole bike feels better.

I have to make another guard for the primary and then think about what color to paint the bike.

 

[msrfan]

I recently put fenders on this bike to give it a different look, along with a longer headlight.
After talking to Danny at 3D Motorsports, I ordered one of his manual clutches and installed it today. It works great. Takes a little time to get used to feathering it like the automatic, but you have total control. I highly recommend it for a go kart type automatic swap. Once I get used to pedal starting, I can remove the unsightly pull start. I also have the option of eliminating the guard because the outer part of the clutch doesn't spin.

 

[Venice Motor Bikes]

The bike looks awesome!!!

How do you think that clutch would hold up on a built 212cc Preddy?

 

[msrfan]

Thanks Norm. Danny at 3D claims it will handle tons of power. I know it will do better on a larger 4 stroke than my little motor. Mine doesn't have the torque of a larger engine, lots of clutch slippage until enough speed is built up to fully engage it. I end up duplicating what my expensive go kart centrifugal clutch does plus total control over more slippage if you need it. There's videos of it on mini bikes and go karts up in the 40 + hp range, but it looked like a 3 disc unit on the most powerful kart. It took me some time to realize why it's hard to get used to. The clutch engagement mechanism is so efficient, you can pull the lever with your pinky. Huge mechanical advantage. I would like to have more feel to it, like maybe stronger springs. That would probably give me the feedback to let me have a better sense of exactly where the engagement begins without releasing it too fast and killing the motor. I have to slip it on every slow down and turn, where a bigger motor would just torque up without disengaging.
Overall I love it and will be going to Donut Derelicts in the morning to give it a good test. Greg and I are putting one on a Briggs bike, but it will be a while before it's rideable. 3D gives great service, fast delivery and good support at very reasonable prices. I highly recommend their clutches.

 

[msrfan]

The bike performed well but there is so little amount of stroke at the hand lever to work the clutch that it's hard to let it out slow enough without it grabbing and jerking.
So I made an extension to get the cable attachment at the clutch farther off center. That gave me lots more movement at the hand lever and resulted in much more control on takeoffs. It's a real pleasure now because I can enjoy the ride instead of concentrating on operation of the bike.
I also installed a muffler at the end of the exhaust pipe and a clamp to the frame. It's much quieter now without a large power loss. I guess it needed a bit of back pressure because it doesn't sputter at top rpms now.

 

[curtisfox]

Awesome! Good to know, how much longer did you make it?..........Curt

 

[msrfan]

Hey Curt, almost 2 inches farther off center. I thought the hand lever pull was easy before. Now it's feather light. I would rather have a good strong feeling lever, but this will do for now.
How's your clutch coming? Looked good so far.

 

[curtisfox]

Slow as summer work has taken over, but will do a little at a time on rainy days...........Curt

 

[msrfan]

I just communicated with Danny at 3D and his E-Z Pull lever has the pivot closer to the cable end that does mostly what my modification did. I may end up with his lever. He also suggested a spring added to my lever to get a stronger clutch feel, so I installed a spring in the cable. Now I think it's just right. I hope all this info helps someone else in their 3D instsllation. Although A larger 4 stroke should be just fine without mods.

 

[Venice Motor Bikes]

Genius!