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The build


I started this blog because it's not always easy to find what you're looking for when doing a build. Don't get me wrong, there's a lot of information out there online about bikes, but it's not always easy to find what you're looking for among the weeds, wrong information & just plain garbage some people pass off as knowledge. Sometimes it takes an hour to get a simple answer which could be just one sentence, but good luck finding it with 5,000,000 search results.


I did some basic research online about a build, but it was hard finding some simple things like wheel & tire combinations, hubs, axles & braking systems. I am by no means a good welder, experienced builder, engine mechanic or bike designer. I've come at this build with a lot of experience in making things, but have no experience with machine shop stuff or much with metal working in general. I was a cabinet maker by trade for residential and commercial construction & have some experience in the aircraft cabinetry industry as well. All of this helps when you have to figure things out in the shop, since we're always building on things we know to make the things we don't know about.


The basic frame has a 51 1/2" wheel base and about 15" between the top & bottom frame rails for the engine. The front "tree" is set with a 35 degree rake, which ends up having a 5 1/4" trail dimension, so high speed handling should be OK, but that needs to be proved in real world trials. I've had it out once on the street, but I still need to do some high speed runs to see how it handles before, I do a real speed run. For now the gearing is set up for 60 mph at 8,000 rpms.


There should be enough room for a big block later on with this frame, but now it has a 212cc Predator motor (the 60363 "Hemi" type) which has been modded to make more horses than the original claim of 6 1/2 hp. It has an Isky Black Mamba cam, Bullfrog Racing 11:1 pop-up piston, a mildly ported head I worked on for airflow, ARC billet rod & flywheel (a MUST for higher RPM stuff!) & a real Mikuni VM22-133 carb, not the "Chikuni" type. There are also heavier push rods & some other odds & ends to make things stay together, like studs in the block instead of the usual factory bolts. Best guess is that it's making about 18 horses now, but that's only a guess based on the combination of parts. Without a dyno, there's no real way I can measure the HP at the rear wheel. I guess I could calculate the top speed as a function of wind resistance, but that's getting into math skills I don't have.


I had some help from JP Rodman with the frame. He's a trike builder here in Raton where I live now & does some incredible show bikes (look him up online). He has a tubing bender & dies for DOM tubing, so I went to him for the bends I needed. I gave him some full size cardboard patterns & he gave me back the tubes. They still needed to be cut to length & then bird's-mouthed for welding, but that's just what it takes for building a frame. I used 1" X .010" wall DOM tubing, which is a bit larger than the normal mini bike tube. Usually, 7/8" X .083 wall is standard for this type of frame, but that's what my supplier in Tucson had (Industrial Metal Supply) on hand at the time. JP had the 1" die setup for his machine to make the bends. It's about 1/4 pound per foot heavier than the 7/8" but it's "strong like buffalo" for a frame, so it's good enough.


The steering head is a 6" X 1 1/2" X 16 gauge tube, which has an ID of 1 3/8" for the bearings. I didn't need bearings for the steering & forks, but it should last forever & tracks really easily the way it's made. The front forks are 7/8" DOM tube & top and bottom plates are 1/8" mild steel. The steering bolt is 5/8" grade 8 & the front axle is as well. The rear axle is a regular 1" X 16" steel threaded axle which is slotted for a 1/4" X 1/4" key. It took a bit of research to find the brake disc, hubs, rims, tires & other stuff to put it together, but check on my build page on the forum to see where I got things.


There are lots of decisions to make when building. The best thing I can say is to look at lots of other builds first, ask questions where you can, & find the parts where you find them. One nice thing about building in a small town, the internet is always available for parts and information. It costs more for shipping, but the availability is limitless. A large city has better resources in general, but also the crime, people & traffic to go with it. For anyone interested, Raton New mexico has a nice life style (slow), really cheap real estate still & a good climate if you don't mind a few months of winter a year. The air, water & people are all great here. The Run To Raton continues to grow each year & brings in people from other areas.





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