I havent had a dirt bike since I was a kid, and would love to dink around on one again. The guy selling it didn't even know what it was. It was listed as "Suzuki dirt bike, doesnt run". He was asking $150, but I knocked it down to $75. Its not in the greatest shape, but I've seen worse.
I noticed right off the bat that the compression was not where it should be when I turned it over. Being an old bike, I figured it just had a stuck ring from old castor oil or something. I hoped it would just loosen up on its own.
Well, it didnt.. I pulled off the exhaust and found this:
So it was time for a top end rebuild. Bottom end and wrist bearings felt perfect, so I left them alone. Found a NOS .50mm genuine Suzuki oversize piston on ebay, along with set of new rings. I did some calling around to some machine shops. Lindsay Machine Racing is the best known machine shop around for this type of work, but they wanted $90 a hole to bore! I called around to some other shops. Most wont touch 2 stroke cylinders, due to the ports. I found some guy that would charge $30, but he didnt sound very confident. Then I called a machine shop that a buddy used for his 22re head work. "Crankshaft Grinders". Very nice, knowledgeable older guy, with some younger kids working for him. $40 to bore it over. The exhaust port had some damage from the rings mashing against em, but most of that got worked out during the bore. He did an awesome job. I took a new ring, and checked the endgap from one end of the cylinder to the other, and it was spot on! I'll be re-using this guy in the future with the CB200 I have. He chamfered the exhaust port, and I chamfered the rest:
Cleaned it all up, a touch of assembly lube, and its time for re-assembly:
The bike immediately had monstrous compression compared to the way it was! It started right up after about 4 kicks:
Thats about it for now. It needs to be broken in. The bike still needs a lot of other work. Tank is rusted out, needs a chain. Tach and speedo are missing, but I dont really care about those. Oil injector is not hooked up, so it runs premix. But it has a pressurized crank oiler, so I should get that working again. Should prolly get a title too
This is the Microbike... I built this back in 2004-2005. This was just before I met Ash. I had a lot of time on my hands.
It originally was a Runt bike, which I strapped an engine to the back with friction drive... it was fun, but I wanted to go smaller. I hacked the frame in half, got rid of the rear suspension and bolted the swing arm on solid. Welded a seat mount to the remainder of the frame. Wheels are goped wheels, which fit well with spacers. Rear wheel is specifically from the Goped GSR (Chain drive model), as you can bolt a sprocket to it. Engine mount was fabricated from weldable steel from Lowes. Engine is a 31cc ryobi weedeater engine, with the covers removed. Flywheel fins were ground down to make the flywheel thin enough to fit in the mount. Front sprocket is the smallest pocket bike sprocket I could find...6 tooth. They come ready to thread onto the clutch they normally mount to on a pocket bike. The ryobi did not have these female threads to accept the sprocket, but does have a long extension off the crank. I cut male threads into the crank. I then found 2 nuts that each thread onto the crank, and the sprocket. I welded these together as straight as I could. It took a couple of attempts, but eventually ended up with a perfect adapter. Adapter screws onto crank, and sprocket screws onto the adapter. I added axle pegs to not only put your feet on, but to also protect the bike from falls. Fuel tank is off some weedeater, I don't remember... added a twist throttle, and modded the exhaust so it didn't shoot into your leg. The seat is a Harley backrest
That's about it! No brakes. No kill switch. No clutch. Direct drive... You push start it, then jump on while its moving. I takes quite a bit of practice to get it right. It is also rear heavy, and likes to wheelie over if you aren't leaning forward. It does about 20mph, which is PLENTY fast for its size. It always seems to gather a crowd when I ride it in public areas. Its also been a tough little bugger... Been wrecked MANY times by different people, and can always be picked back up and ridden again.
Lots of things fixed on the bike so far:
- New triple tree clamp.
- New levers.
- New grips and throttle twist. (Had the wrong one installed)
- New ram air ducts, and boots.
- Made a new bracket for the front brake reservoir.
- Fixed the choke (creatively).
- Fixed the passenger seat lock release cable.
- New right passenger peg.
- Removed the ghetto mirror and front blinker relocation. Will be putting on flush mount blinkers.
- Knocked the bondo plugs out of the original blinker mount holes on the fairings.
- Spent 2 hours restoring the hacked up front harness to new condition, then Penny destroyed it. (Gotta get another now)
- Removed all the ghetto taillight/plate bracket crap. (This was especially Ghettofabulous!)
- Began attempt of stripping the paint off the windsheild with DOT4 brake fluid. I hear it doesnt harm plastic.
- Replaced numerous missing bolts holding plastics together.
- Some cleaning.
- Its also now temp registered, insured, and new title arrived.
Still plenty to do, but getting closer. Waiting on many parts still. I took the bike for a longer couple of rides. Runs amazingly well dispite the cosmetic abuse!
I pulled the carbs, and cleaned them Saturday, but it still didnt run right. I noticed there is a vacuum line coming off the #3 intake manifold with nothing hooked up. I plug the line and it revs SOMEWHAT better. There is also another disconnected vacuum "T" underneith the carbs. Connected them together, and it revs out fine now.
Take it for a spin, and it still isnt right... Missing a lot, and mostly running on 3 cyl. Pulled the coils and made sure they were clean/dry.... No go.
The vacuum lines that I connected together didnt fit snug, and I had a feeling that these dont connect together. I look in the manual, and find the line coming off the intake actually goes to the bottom of the fuel petcock, as its vacuum actuated. However the nipple is broken off the valve! The next day I realized the bottom half of the petcock looks VERY similar to the one on my old 82' GS750EZ. I had a couple of spares, and I removed the bottom to see if it fits the gixxer's valve. Not quite, the holes were off by about a half a MM. Drilled the holes out slightly bigger and it fit. Screwed it onto the gixxer's valve, and tested using my breath. It works! Put the tank back on.
That sorted out the fuel valve, but I still didnt know where the T junction vacuum connector goes that comes off a pair of solenoids on the bottom of the carbs. The manual does NOT mention these! After some looking around I see a drain on the bottom of the airbox that has a small hole at the bottom. Bingo, that isnt a drain, its where the vacuum hooks up.
Took it for another spin, and it now runs GREAT!!
Now I just need to take care of the cosmetics, and a few other things. I've already ordered about $250 worth of parts on ebay to get started.
Well today I finally got a hold of a guy on craigslist that was advertising "GSXR Project Bike, Needs work" No price, year, model, or contact info. After a couple of days of emailing, I find its a 2000 GSXR 600 that he cant get started after it sat all winter. I finally get a phone number, and tells me $350 if I take it today :O
I head to Park City right after work, stopping @ an ATM on the way. When I get there, the douchfag raises the price to $400! "Dude, I gotta get $400 cus my Bro will give me $500". I stuck to my guns, and managed to get it for $357 (gave him an extra $7 in my wallet).
Here it is on the way home:
The whole bike is hacked up bad. Wiring, just about everything cosmetic, blinkers, exhaust, everything is bad shape. Blinkers are screwed in on the sides of the plastics in the wrong spot, top triple tree clamp has huge holes on it, etc. etc. etc.
After unloading I go straight to work. Ignition comes on, but no crank. So I take a jumper cable and jump the battery straight to the starter. It now cranks, but still no life. Pulled up the tank and yanked the airbox. Manually choke the carbs with my hand, and there is fuel, but still no fire. Pulled a plug, no spark. Started poking around the wiring. The wiring on this thing is hacked up pretty bad. But I did find a burned fuse! After jumping the fuse, I hear a relay click, and the fuel pump kick on. Bingo! Spark! I throw the plug back in and it fired right up! Runs like CRAP but it runs. Carbs need rebuilt badly, but luckily I have a spare engine with carbs for parts! (I have a 98 GSXR600 motor that was going to be a kart project, but it never happened)
I even took it for a quick spin tonight, and it rides good!
Here is a quick video:
Still LOTS of work to do!