Bored Rat Racer

[Mobbin'Deep]

Here is my bike...

Before:

After:

1982 Schwinn Cruiser made in japan
Modified Frame
Built 66cc Gt5 Ported
Puch head
Advanced Timing Ngk plug
Handmade intake
Dax rt
SBP pipe
40t
Suzuki forks Rebuilt with repsol oil
Weinmann wheels



Runs stellar, makes good power, clutch doesn't quite hold it, but it still is ride-able. Have done indicated 38mph whilst breaking in. She is the best china girl ive ever built or rode.

Plan to increase compression once broken in, and figure a way to get this clutch to grab, add a 36t, and some front brakes! lol

 

[MotorBicycleRacing]

Yep, you need front brakes! Great lookin' race bike.

 

[cobrafreak]

Nice style dude.

 

[darkhawk22]

Nice build so far for sure! One of Sportcarpats (sportman flyer) in frame tanks would look great in that frame if it would fit!

 

[vachon644]

I love the frame and how well the engine fits in it with the expansion pipe.

 

[\./]

how do you add compression?

 

[Mobbin'Deep]

Nice build so far for sure! One of Sportcarpats (sportman flyer) in frame tanks would look great in that frame if it would fit!

Thanks! I am gonna make a sheet metal tank to live in the frame, but got so impatient that I HAD to run my motor. I got this "craftsman" tank from a 82yr old guy i found on Craigslist who has a small engine grave yard at his home. Had a box of these kind of tanks haha. Sold it to me for $4

I love the frame and how well the engine fits in it with the expansion pipe.

Thanks! It took a while, Alot of trial and error of trying to balance Form vs Function. I wanted that drop loop style, so if you cross your eyes a little bit the expansion looks like part of the frame.

how do you add compression?

Either by decking your head or top of jug (remove material) or buy a high compression head.

Update pick!

Almost done with break in! whoohoo!

 

[spanners]

Very nice looking bike you did a fine job on the upside down forks. For me puch hi hi 50's was the way to go but getting the cluch to grip was a problem.

 

[Cycoracer8]

Nice racer dude. I was wondering how you where figuring in the break in on your engine. Hours or miles? I use to race Harley's & would build them one day & race them the next. Built my engines with race clearances so break in was very minimal time wise.

 

[Mobbin'Deep]

Nice racer dude. I was wondering how you where figuring in the break in on your engine. Hours or miles? I use to race Harley's & would build them one day & race them the next. Built my engines with race clearances so break in was very minimal time wise.

I ran about a galon of 28:1 with light load. Then switched o 40:1 Repsol 2 stroke competition mix. And she RIPS, smoother, slightely quieter

 

[haste]

bike looks sick, you use stock mounts?

 

[Mobbin'Deep]

bike looks sick, you use stock mounts?

Thanks! And **** NO. I've had nothing but problems with the straps, clamps, and even SBP mounts, i broke two of those in the past. Plus a bunch of hardware. So I went overboard this time.

Fully welded with vibration isolators.

Heres my brothers new toy we just picked up 2nite. $500 and it runs good but carbs need love.

We rode to the gas station down the street, and i was smashing on him. Was a blast haha. Around town its hard to beat a MB

 

[haste]

ah is it like a motor mount piece wedged between that and the motor?

 

[Mobbin'Deep]

ah is it like a motor mount piece wedged between that and the motor?

No no no. The less you use the CHINA hardware the friggin better. There is almost no china hardware on this motor.

The thing you think is the strap is a vibration isolator.

It has a bushing that the bolt rides in, and the steel clamps to, but is surrounded by polyurethane. There is no actual metal on metal contact between the motor and frame. The the Poly Isolates the vibes and turns it into low level heat.

So far its working well, vibes are noticeable, but not painful in anyways, on your nards, or in the bars. Its the softest ive ever felt.

 

[Mobbin'Deep]

My SBP pipe needed modification... The rivets used to hold the aluminum muffler pipe on loosened themselves up. It was leaking horribly. Rather than replace the rivets...

I made a muffler pipe out of 18g steel, then welded it closed, welded it to the expansion, then welded the muffler tip to the pipe. No more leaks.

bikes running good. But ive decided not to spend anymore money on it. Thinking of swapping motors when this one goes.

 

[haste]

Going 4 stroke...?

This build wants me to build a tuned, legit Chinese 2 stoke but your last comment makes me just want to go 4 haha.

 

[Mobbin'Deep]

Naw, i like thumps but cant afford a super legit setup atm. 2 strokes are cheap powa.

 

[haste]

Any issues at all once you have replaced everything with legit parts?
What throttle you running?

 

[Mobbin'Deep]

The only issues im having are:

Clutch engaging problems
Hard to start (high compression + clutch slip issue)


The clutch wouldn't hold the power at first, it would slip, ALOT. Now ive adjusted it alot, new pads, cleaned everything, scuffed up pads...

Now the clutch slips when the motor is cold, It makes it really hard to start, pedal as fast as you can dump the clutch and nothing happens...BUT when you get it started, and warmed up, the clutch bites hard, can go full throttle at any time...

Im pretty burnt out on messing with it. I have waaaay too many hours into this bike. I know its a china girl, and she runs great, makes good power, but it seems like every time i want to ride, every single time, i need to adjust something. Im losing weight pedaling so much haha

The throttle housing is off of a kx500 or something. Got it from cycle salvage, they have boxes of old throttles and what not.

I MIGHT BE PARTING THIS MOTOR OUT!! stay tuned

 

[haste]

Ah, bummer.

Seems like 4 strokes are the way to go nowadays. Reliable, torquey, and agk sells great performance upgrades.

Only downside is more parts, and a heavier bike.

 

[The 26incher]

I didn't read this whole thread but 82 SCHWINN made in Japan? Never hear of that! If it's an 82 it's US made...