09APR2011
I guess it is time for another update. I found and fixed a small electrical mistake I made, it only cost me one bulb to find. The jetting is getting very close to being correct. Dialing in the jetting has been tougher I think since the bike never was at 100% when I have rode it, so I am always worrying that I am expecting too much from what is now a 80cc motor. I also repacked the silencer, it was partly because it had blown some packing out, and partly because I had the stuff sitting around to do it. I think a change in gearing might be in the cards soon, first gear is super short, almost useless really, it would be great off-road but as a pit bike and city runaround I think I will loose some low-end for more top-end. I rode it for the first time today in traffic to the gas station, it has been a long time since I put only $2.50 of gas into a bike.
Currently the indicated top speed on a flat is 30 mph with me riding it, I weighed in this morning without gear at 220 lbs.
12APR2011
More Mini-Trail news, I have been finding lots of reasons to run to the corner store on it for testing. Anyways I swapped out the 13t front sprocket for a rather hooked 15t I had sitting around. I figured with first gear so short I would test some new gearing. With the 15-35 gear ratio (stock is 13-35, and the first few years of production ran 15-35) I was able to hit 35mph on the flat before I ran out of road. I now plan on ordering both a new 15t front sprocket as well as a 16t on my next parts order. On the jetting front the 68.5 main seemed to be working well, but I did a test run with the 70 main and it was definitely running rich with that, so the 68.5 will go back in. The big issue I need to address at the moment is the swingarm pivot bolt. There is noticeable lateral play in the swingarm, hopefully a new bolt will resolve this. I also need to install the brake light switch and replace the tail light bulb. I burnt out the 6v bulb due to the wiring mishap I mentioned earlier and have a 12v (1157) in it now, it glows but not as bright as it should.
The bike is almost to the point of being semi usable transportation. I am now aiming for 40mph on a long straight as a top speed, I think with regearing it will be possible. To be honest I am not sure if I want to go much fast than that on this bike, the tiny 3" drum brakes are touchy at best.
Another build of mine with slow updates. I have hinted and some people of sneaked glimpses of a seat I am working on, I will show that to the masses. The biggest update is in the seat set-up and battery relocation. When I last ran this bike I had the battery mounted on the swingarm in front of the tire using the tool box mounting points. Prior to the seat being made an under the tail batterybox was fabricated. I have noticed after preview this it does not come close to conveying the time this took.
I still need to clean it up, round the corners and grind the welds mostly, and hit it with paint. Anyways it was complete enough to proceed with the tail section.
Motivated by a post I saw about making a seat, and the lack of desire to order another one from AirTech (great product, but hard to judge how it will luck before ordering) I proceeded to make one. Armed with a pile of fiberglass supplies and a KZ440 tail section I started.
Wrapped in tin foil.
Base coats.
Roughed out with the KZ tail section mocked up.
Roughed out.
After laying a bunch more fiberglass and trimming, it was time to let the dust settle.
Starting to look like a seat.
Ugly underside.
Getting there.
And another coat...
On the bike.
Primed and mounted
I am still working on working cleaning up all of the little imperfections in the seat. I plan on painting it semi-gloss black (as I have no easy way to match the Norton British Racing Green on the tank) with white numbering backgrounds and hand painted “603” (my VMX race number) numbers on it. I generally think numbering non-race bikes is silly, though I do give a pass if it is the same number of the other race bikes in a garage. I will probably have Thrasher Bill do some striping as well, nothing fancy, just the traditional style coachlines separating the colors and highlighting the numbers. I already have stick-on closed cell foam to pad the seat. To be completely honest if I was to do this over again I would have just ordered another seat from AirTech. Though I am totally happy with the seat, it would have been cheaper to buy one, that is before factoring in the countless hours of labor.
Small update here. Over Christmas I went back east and was able to get the paperwork in order to plate this fine machine. Now I have a collectors plate on the bike. Also I got the seat back from Thrasher Bill, with its new sexy cover. Real tuck-rolled top, sweet yellow piping, and many dead naugas were used for the sweet brown covering.
Now that I have a seat again rejetting should come soon. I am looking forward to more speed trials, legally this time.
