Jdogg's scratch built Frijole anything goes 2016 OldMiniBikes build off entry

jjdog, I decided to build a minibike with an engine similar to yours and then came across your cool ride on this site. Your pictures are every helpful, and your build helps me to better consider my own ideas, and what I want to do. I had already been thinking about the same color you used, and can really appreciate you are paying tribute to the color of some of the GT40's. Back in the day when they were racing, I painted my bicycle the same blue because I was such a huge fan of the GT40's and Cobra Daytona Coupes. Now, I'm considering going with the scheme used on the Lotus 25 Grand Prix cars. The frame would be green, with a red seat and yellow wheels.

I'm wanting to use a 125cc engine with 4-speed gearbox and electric start. Not that I can't use a kick starter, but it would be extra nice to be able to just turn a key! The only engine with electric start I have found available in the U.S. is the Loncin from Peace Chopper. Are you at all familiar with this engine? Also, even though you designed and built your own rear wheel/sprocket, have you seen a six-inch wheel available from a supplier that has spokes and will withstand the torque from a geared engine such as yours? Where did you get your wheels? Again, thanks for posting your inspiring build!
 
Hey Aston! I would love to see you do the Lotus 25 color scheme on a mini bike!! As for these Honda 125cc Knock offs I am not familiar with the Loncin but I have a Lifan on my pit bike, a Zongshen (which is on my Frijole) and a unknown to me make on a mini crotch rocket which runs great and they all seem to be of the same quality which to me is OK!! I haven't ran across one yet that I couldn't get running with a little tinkering or a new CDI unit!! The Lifan seems to be better spoken best of as far as quality control though.....can't really say for sure which 6'' wheels can actually handle it as Iv'e heard of even the Astros breaking up before.....might want to try and start a thread in the general mini bike section to get more people to chime in on that topic! I bought my wheels from OldMiniBikes.com here:
https://www.OldMiniBikes.com/Mini-Bike-Go-Kart-Parts/Wheels/6-Wheels
 
Hey Aston! I would love to see you do the Lotus 25 color scheme on a mini bike!! As for these Honda 125cc Knock offs I am not familiar with the Loncin but I have a Lifan on my pit bike, a Zongshen (which is on my Frijole) and a unknown to me make on a mini crotch rocket which runs great and they all seem to be of the same quality which to me is OK!! I haven't ran across one yet that I couldn't get running with a little tinkering or a new CDI unit!! The Lifan seems to be better spoken best of as far as quality control though.....can't really say for sure which 6'' wheels can actually handle it as Iv'e heard of even the Astros breaking up before.....might want to try and start a thread in the general mini bike section to get more people to chime in on that topic! I bought my wheels from OldMiniBikes.com here:
https://www.OldMiniBikes.com/Mini-Bike-Go-Kart-Parts/Wheels/6-Wheels

Thanks you for your comments and answers! Based on your video of riding the little rocket ship it sounds like your gearing is good on the low and high ends. Are you happy where it is? Could you please tell me what number of teeth are on all of your sprockets? I see that a you can adjust your final drive chain tension by moving the jack shaft. Does your engine mount move for purposes of adjusting the first drive chain? Where did you get your disc brake components? Thanks for your patience with all of these questions!
 
You are very welcome and I am glad if I can help you out!! I am really pretty happy with the gearing and as you stated it does have good high and low end....my pit bikes low end always seemed too low and made we want to skip first gear all together!! I'm running a 15t off the engine to a 15t on the jack shaft input with a 15t off the output to a 33 on the rear wheel! These can be easily and cheaply changed and messed with to suit your riding needs!! The jack shaft was added so I could add the disc brake and give a shorter run of chain! I am happy with the gearing as 1st gear seems useful now and fourth does not lug! I'm about 185lbs! Yes Sir the engine mount is slotted on the engine plate for tension!! Disc brake parts were easily sourced on ebay:

Rear Disk Disc Brake Caliper for Baja Doodle Bug Mini Dirt Bike 97cc 2 8HP DB30 | eBay

These rotors are a little smaller than the DB30's and I'm not sure this is the exact size I used....but i just centered and welded to the jack shaft gear!

120mm 29mm Gas Scooter Brake Disc Rotor Pocket Bike Electric Mini Dirt ATV Quad | eBay
 
Yup went out and measured the rotor as best I could cause the jack shaft gets in the way and its close to 6 1/2'' not the 120mm like the link I posted! The bike stops pretty good with the mechanical calipers but would surely lock it up with the hydraulic conversion from hotrodminibike.com!!
 
I think that if you look a little more you can find a better deal.
I agree with Yalipito !! You can find better deals out there! Aston are you looking for this brake to be a front, rear or jack shaft brake? Some of those hydraulic cables are too short to reach the rear or jack shaft areas. Heres a few:

You can do something like this and mod it to make it foot activated:

Rear Disc Brake Assembly Master Cylinder Caliper 125cc 150cc Dirt Pit Bike ATV | eBay

This ones not bad but the inner diameter of the disc might be too big to adapt to a jackshaft sprocket like I did if you are going that way....and the hydraulic line if not long enough may need to be replaced!

Dirt Pit Bike Parts Front Hydraulic Brake Caliper w Pads Disk 125cc 150cc | eBay
 
Thanks for the input, gentlemen. I agree that these look like better deals. I am purposely waiting for my engine, frame and jack shaft to arrive before I buy brake hardware. The first thing I want to do is work out the basics. Of course, then I can determine how long my cables or lines need to be.

I have been planning on a jack shaft mounted brake. The idea of a foot operated brake is intriguing. Jjdog, it looks like your bike has the rear brake operated by the lever on the throttle hand side, like a conventional motorcycle. After using that for awhile, are you thinking a foot operated brake would be better? By the way, your mention of a front brake makes me curious about that, but I guess I probably won't have room between my front forks to mount one. Do you feel like your rear brake alone gives you good enough stopping power?
 
Hey Aston!! You're very welcome!! The jack shaft mounted brake is operated by the right hand lever ...while not bad I would like a little more if I actually got to ride it more frequently..it stops OK but won't lock it up if needed....a foot operated brake may help to apply more pressure but the hydraulic conversion would be a direct bolt on from hotrodminibikes.com as it uses the same mount....I may go that route some day!

Hydraulic Brake System
 
Thanks, jdogg. That looks like a good way to go. I just sent them an email to see if I could get the system with a chrome or otherwise metallic finished lever.
 
Hey jdogg, what kind of welding and welder are you using? I just ordered a tachometer. It reads up to 8,000rpm, just right for the engine I ordered. It is electric and will allow for single-cylinder use. I'll probably make a small dashboard with the tach centered, and a starter button on one side and a blade-style ignition switch (no key) on the other side. What sort of ignition switch are you using? I suppose I should probably have a kill switch on the handlebars, but I don't really want to.
 
jdogg, did you weld your frame together using MIG or flux-cored wire without the gas? I've built quite a few things over the years but have always been able to screw, bolt or rivet parts together. i always thought it would be great to be able to weld, but am not knowledgable about it. I'm deciding between using a fab shop nearby to weld for me, or to get a welder and do it myself.
 
Aston I use gas always.... never tried flux core, but I hear its not too bad! Give it a shot and practice practice practice!
lots of great beginner welding videos on youtube!! Always great to learn a new skill!! :thumbsup:
 
jdogg, today I went to look at welding equipment at a local supplier and found that it would cost about $1,000-1,200 there to get everything for a 110V input MIG set-up. Maybe I will get a flux core set-up and see how I do. They are pretty cheap, as you probably know. Thanks for the encouragement and input regarding flux core.
 
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