4 stroke btr build

[meatgrinder]

so after tackling with 2 stroke china dolls, finally decided to take the challenge of building a non-kit, 4 stroke 196cc 6.5hp board track racer. will document my build and to start with, here's the frame and the heart of the beast

1950's straightbar lugged frame

196cc 6.5hp 4-stroke engine:

im planning to use this flip flop hub for the sprocket adapter and use a mountain bike disc brake adapter and thread it to the drive side of the bike. would you guys think it would work?

i'll keep you guys posted on this build

 

[MotoMagz]

Looks like your off to a great start! Once you go to the 4 stroke you won't go back.

 

[wret]

Someone correct me if I'm wrong, but I believe flip flop hubs aren't designed to be driven from the the left side and the hub would unscrew itself.

 

[meatgrinder]

decided to take off the blower housing and the carb. the plan is to swap the stock carb to a new 22-24mm mikuni carb and fab my own intake manifold.

 

[meatgrinder]

thanks MotoMagz. im really looking forward to the power and reliability of these four stroke engines. plus, i like that muscle sound of 4 strokes

 

[meatgrinder]

@ wret - yes you are right, im planning on using the drive side which is the right side so it wont unscrew itself. im planning on using a mountain bike disc brake adapters

 

[Moisstink]

I am planning on doing the same for the same reasons. I have 42 Roadmaster and a 56 Briggs and Stratton. ****, I was going to wait a little longer to start the thread but their is a wealth of info on this site that I am going to need to tap as well.

 

[curtisfox]

Interesting got to watch this and see how you go about it. Like it so far..............Curt

 

[meatgrinder]

Sorry to post late, haven't got much time to work on the bike due to $$$ issue. but got it sorted out immediately. Started on the frame and cut it in half. feel kinda sad about cutting this frame in half but then realized that it would look way cooler once the drop loop is added.

 

[meatgrinder]

took the frame to my local fabrication shop and gave the specs and drawing for bending and welding (rubbish drafting skills i know) sorry for the LOW ASS Quality of the picture. only got my phone cam and left my camera

getting there. just needs a bit of weld and cutting and this thing will start to look like a board track racer

 

[meatgrinder]

And as of now, heres the frame with the drop loop and the 7" extension. still needs a bit of grinding and cleaning up of welds and i'll start the motor mount.

 

[anota]

I have that same frame and hate how tight it is! I think im going to have to copy off your build because I love how it came out! Was the frame mig or tig welded??

Cheers

 

[KCvale]

I have that same frame and hate how tight it is! I think im going to have to copy off your build because I love how it came out! Was the frame mig or tig welded??

Cheers

Way off topic but nice photo wall anota, so few people take the time to consider the background of their bike pics that I take the time point a nice pic when I see one ;-}

 

[magna_503]

signing on for a great background, as i'm guilty of bad back ground all the time... .

 

[meatgrinder]

I have that same frame and hate how tight it is! I think im going to have to copy off your build because I love how it came out! Was the frame mig or tig welded??

Cheers

thanks mate! yeah the frame really is a tight fit so the 7" extension shouldn't be a problem and the drop loop did the trick fitting the 196cc 4 stroke honda clone in there. the top tube 7" extension on the frame was oxy-acetylene welded. the down tube/ drop loop modification was oxy-acetylene welded at the top then arc welded on the bottom bracket. I'm currently machining the clutch, sprocket adapter and welding the motor mount. i'll post pics real soon.

 

[runnermike]

Looking very nice! Cannot wait to see the finished product. Where did you purchase the engine from?

 

[meatgrinder]

went to work on the bike a few days ago, just got my cam and took a snapshot of whats the hub & the sprocket adapter im working on. im planning on doing a freewheel sprocket 36t and a disc brake on the rear. im using a flip flop hubs.

here, i just placed the 16t freewheel cog to the center of the 36t motorcycle sprocket and it fits like a glove with no problem. im gonna weld the 16t cog and the 36t sprocket and simply screw it on the right side of the hub.

 

[meatgrinder]

and hopefully, the result will be nice. still thinking if the freewheel cog can handle the torque of the 196cc motor and it better hold up good!

 

[meatgrinder]

Looking very nice! Cannot wait to see the finished product. Where did you purchase the engine from?

thanks mate. i got the honda clone engine from a local engine / farming supply store here in Manila. cost me around 3,500 pesos roughly around $80 USD.

 

[runnermike]

Looking good. Hope it holds up for ya!