r/projectbike

Posted in December about the new project I got. 1975 Kawasaki g5. Was expecting a simple project of clean the points, carb clean, and set to go. We all know how that goes though. After a while of struggling to get it to run, came to realize that the flywheel side crank seal was completely blown out, and the cause was the totally destroyed crank bearing underneath. Well, out with the motor, and a full rebuild ensued. Top end revealed to be a huge problem too! The bike had great compression so I had no suspicions until taking it all apart, but the piston was severely scored and the top ring was missing a large chunk. I’ve done many top ends in years past but this was my first case split/full rebuild so it was a bit intimidating at first, but it went well! All brand new OEM bearings, gaskets, and other random bits, wiseco piston kit, hone of the cylinder (which somehow survived completely unscathed) and reassembled. Some jetting and tuning, little electrical work, and yesterday went on its first trip down the road! What a fun little bike. A lot zippier than I expected!

Hello!

I am looking for some advice.

After having my motorcycle license for 12 years I finally pulled the trigger on my first bike; a 1981 Kawasaki KE100. Aka a glorified moped that makes cool noises.

Purchased it non operational, prev owner said carbs just needed to be cleaned and fresh gas. Not afraid to get my hands dirty (never worked on a motorcycle) because how hard can it be? I got her idling after doing just that, a new fuel line and a new petcock.

The day I was able to get it to idle, decided to drive it around the parking lot. During the short 5 min ride, there was no power, running very lean, then would not run off of choke at all. Know it was an air issue, I couldn’t figure out why after countless YouTube and ancient forum threads… I was starting to lose hope… then my heart sank.

I started to see oil seepage/dripping after I parked it. I couldn’t tell from where. After cleaning off the bottom of the crankcase, I noticed a small hole the size of a flathead on the LH crankcase. I drained the oil to find metal flakes but no chunks.

I have yet to remove the engine as I am still a beginner but it’s looking like I’m going to have to remove it and even split the case at some point.

This is starting to become way more intrusive than I anticipated.

What are my options? Weld the case and fill the hole? JB weld? I’d be willing to try anything at this point. I just want to get on the road, man! I’m hoping to find a more cost effective and timely solution than a total rebuild. Located in CA, USA.

Thanks for any advice 🤝✌️

Looked like the old owner got a .5 over kit and never checked the top ring gap, wiped out the ringland and took the cylinder out.

The bottom was in such good shape, regular oil changes were a visible with almost 0 oil stains inside the casing and no gloop build up in tight corners ect and the pickup was extremely clean so a great find for free

Just got the first start in last night, the code has a few issues with such a geometry shift but just more work to do

Doesn’t run yet, ordered a new battery. Still got some fun photos. Picked it up for $250 and didn’t really plan on getting a bike, but I saw thing on FaceBook Marketplace and figured why not. Clean title too.

A bit of history on the build, My dad is somebody who HAS to build something to keep himself busy. One day way back in 2016 he came across a wrecked 92' 600 and decided that he could get it to run again and better than before. Over the course of several years (working on and off the bike) he combined the 92' CBR 600 F2 chassis with a F3 motor swapped in, the front end (forks, triple tree, brakes, wheel) from a 2007 GSXR 600 and the swingarm from a 1990 VFR750. Along with that while he left the clutch lever and grip is from the CBR alone the right is from a Yamaha he had lying around. To continue to push the build further he custom made the tail section of the bike and included sequential turn signals.

After he completed it around 2021 he test drove it about 5 miles and put it away in a garage he frequented, dismantling it to "save" the bike from others that would probably ride and abuse it. Now here's where I come in. About 3 weeks ago I got curious about the whereabouts of this bike, one thing led to another and I made a combined 1800 mile / 30+ hour trip to go get the bike from him with plans to ride it and enjoy his work that he put in, as he put it himself "it makes me happy to have saved the bike for you, just go over everything and ride safely". As of yesterday I was able to rebuild the bike and get it started up with very minor problems. I'll continue to do my proper checks on the bike as my left hand is recovering from a broken pinky bone (work related) after which I'll take the MSF course and proudly ride the bike!