I wanna build a drag mini/pocket/supermini bike

[beansdaddy78]

Hey guys, i have never done a custom build or even a serious fabrication, just a few small fabs. I am looking to take a pile of junk and make something BAMF! and was wondering if someone who has some experience making or fabbing bikes might be able to get me started with some opinions. im gonna make a list and add some pics of what i have and hope that someone will spend some of their free time helping me with my build. here is a list of what i have to start with, frames i mean

CAteye pocketbike frame, has motor that runs but i wanna swap that motor out with something much faster. also would probably want to lengthen the frame if thats the best choice

1969-1971 Scat Cat SC86 frame, needs front fork but i have a set of forks off a 69 honda trail 50 that look like they will fit with slight mods.

one of them mini pocketbikes, its a knockoff of a Blaze but it has the motor that is only a 40cc i think and it was marketed as a 47-49cc, they lied. this bike also has a running motor but is tiny and im not sure that even lengthening the frame would help.

I also have a bare bones honda trail 50 or 70 frame, needs forks but im pretty sure the forks i have will fit it.

im 6' 210-230lbs (depending on time of year, i run heavy in the holiday months)

im gonna get some pics of them up in the morning, maybe that will help someone give me some advice, hoping someone will at least offer a opinion or suggestion, i have pretty much decided i wont be using the mini pocketbike, but could use parts from it if i need them

 

[exenos]

Man do I feel like a bone rack. 6' 140#

At your size even a 6.5 won't be able to make the bike feel fast without a CVT. As for using the pocket bike frame, take a look at nikogrs bike in the project gallery. He managed to jam a clone into one and make it look amazing.

 

[beansdaddy78]

Man do I feel like a bone rack. 6' 140#


oh and i heart men

At your size even a 6.5 won't be able to make the bike feel fast without a CVT. As for using the pocket bike frame, take a look at nikogrs bike in the project gallery. He managed to jam a clone into one and make it look amazing.

140#s ah i remember those days, fitting in skinny jeans and wearing skimpy baithing suits. them were the days. and then i hit puberty and blossomed like a beautiful butterfly.

i got a few 2 strokes that i could hop up, got a couple macs and a tecumseh power products ah-58, i was thinking i might toss one of them on there, i have two carbs i could use on one mac if i buy a dual manifold. supposedly those 2 strokes are decent power plants, the kinds they used for vintage karting. even though i have never ran one, im in the process of gettting the macs up to standards, since i took the motors off of chainsaws, the ah58 i may try to barter to get my macs outfitted with proper hp parts

my go karts have 5hp motors and they all seem to do ok moving my mass. but i guess if i need to i can try to mount dual macs or something. but thats the reason i am asking for opinions and advice. so that i dont waste a ton of time making something that wont even move me.

thanks for the input

im gonna get a list of motors i have available for this project, and maybe with mods i can get one or two to do the job. id like the thing to be able to pull the tire off the ground. ha ha i know if i want that im so heavy just lean back but thats not what i mean

 

[landuse]

Hey guys, i have never done a custom build or even a serious fabrication, just a few small fabs. I am looking to take a pile of junk and make something BAMF! and was wondering if someone who has some experience making or fabbing bikes might be able to get me started with some opinions. im gonna make a list and add some pics of what i have and hope that someone will spend some of their free time helping me with my build. here is a list of what i have to start with, frames i mean

So you want to take a bare frame that you have already and make something with it, or do you want to fabricate a frame from scratch? You could always do what I did with my minibike (the link is in my sig) and cut a frame in half if your motor doesn't fit properly. I have a 3.5HP on mine, geared to 11.3:1 (or something like that). I weigh about 180lbs and it gets me around nicely.

140#s ah i remember those days, fitting in skinny jeans and wearing skimpy baithing suits. them were the days. and then i hit puberty and blossomed like a beautiful butterfly.

Not the speedo vision again. I just can't seem to get that out of my head!!! "A beautiful butterfly".....LOL. I know some gal that might be interested. Nudge nudge, wink wink

 

[beansdaddy78]

So you want to take a bare frame that you have already and make something with it, or do you want to fabricate a frame from scratch? You could always do what I did with my minibike (the link is in my sig) and cut a frame in half if your motor doesn't fit properly. I have a 3.5HP on mine, geared to 11.3:1 (or something like that). I weigh about 180lbs and it gets me around nicely.



Not the speedo vision again. I just can't seem to get that out of my head!!! "A beautiful butterfly".....LOL. I know some gal that might be interested. Nudge nudge, wink wink

yes i have a couple bare frames , im gonna start with an easy build, if that goes well i have another in mind then if i ever finish that one i feel ill be a fabrication god so ill be able to handle a from scratch build. baby steps to greatness!

is the briggs geared inside the case that way???, someone told me that my briggs 3.5 had one and it probably wouldnt be much fun, i want the thing to fly. I was considering one and maybe dual macs if it can even be done (by me)

oh, your cruel man. my mommy said everyone would have forgotten about that by now. but apparently, she was wrong

in your visions, is my back shaved ??? mmmm

 

[landuse]

is the briggs geared inside the case that way???, someone told me that my briggs 3.5 had one and it probably wouldnt be much fun, i want the thing to fly. I was considering one and maybe dual macs if it can even be done (by me)

oh, your cruel man. my mommy said everyone would have forgotten about that by now. but apparently, she was wrong

in your visions, is my back shaved ??? mmmm

When I mentioned my gearing on my briggs, I was talking about my gearing using a jackshaft as well as my rear wheel sprocket. I am not too sure about Briggs 3.5 having gears in the case. I have heard of one like that.

Oh, and mommy was definately wrong on that score!! It won't be forgotten.

As for my visions......I am going for therapy, so I don't want to talk about it.

 

[Amped]

Posts a few pic of the frames and you will get more advice. What size are the 2 strokes. I've seen a few drag minis that use gx200 built to the gills .

 

[exenos]

Well...


That's an interesting conversation to wake up too. Good thing I dint check this before I went to bed, otherwise i'd probably have had dram with large hairy guys in speedo's, enough to give you nightmares.



Those macs, are they from chainsaws?

 

[beansdaddy78]

Posts a few pic of the frames and you will get more advice. What size are the 2 strokes. I've a few drag minis that use gx200 built to the gills .

the two strokes are

2 McCulloch MC49 (converted from saws) 80cc

1 Tecumseh Power Produtcts AH-58, i have been told several different CC's for this motor but the average is between 90-95cc's

im currently in the process of building the two mac's one is frozen up, so i may buy a dual intake manifold for the two tillitson carbs that i have that go to the motors. supposedly the motors are pretty fast for vintage karting so i figure it would be quick on a mini.

my phone is all messed up for some reason, so it wont let me upload pics to the forum, and when i email them from my phone to my computer they take hours sometimes days. I worry that my phones security may be compromised so i wont hook it directly to my computer for uploading.

i have already emailed them to myself, so im just waiting for them to arrive now so i can post them from my puter

 

[beansdaddy78]

FInally the phone let me post some pics of frames

Hopefully this will help. I'm leaning towards tye scat cat, its a 69 or 70 but it was made in Taiwan and they made a lot.

I think I like the scat cat for a drag bike because there is a lot of room for the motor, I plan to use a regular old centrifigal clutch, maybe not for sure yet. Kinda waiting to see if you guys lift recommend one frame over the other,. Basically the scat cat or the cat eye. I have the body to the cat eye also.

 

[exenos]

I think the middle one would be the easiest to fit a larger engine into.

 

[carter]

If you want a drag bike, you might want to get something with a CVT or a gearbox, a centrifugal clutch won't yield the best performance if you're after what you'd classify as a drag bike.

 

[exenos]

A good cent clutch will work better for a drag bike than a CVT. There must be a reason that racing karts use clutches instead of CVT's. its because of the massive power loss from a cvt (~20%)

 

[carter]

A good cent clutch will work better for a drag bike than a CVT. There must be a reason that racing karts use clutches instead of CVT's. its because of the massive power loss from a cvt (~20%)

But wouldn't a decent gearbox be better than a good cent clutch?

 

[beansdaddy78]

A good cent clutch will work better for a drag bike than a CVT. There must be a reason that racing karts use clutches instead of CVT's. its because of the massive power loss from a cvt (~20%)

that middle one is the Cateye fs509. i agree with you about the clutch, would a stinger be a decent enough clutch?

the cateye seems like it might be longer, im gonna find a couple wheels in the am, to put on the blue frame so i can measure aproximate length.

 

[exenos]

I cant really comment on what would be a good clutch. You'd be better to ask around on a racing kart forum.

But wouldn't a decent gearbox be better than a good cent clutch?

There is still a power loss and when your dealing with hp in the single digits you need everything you can get.

 

[beansdaddy78]

also i just realized i nearly have most of a 1969 honda 50cc trailbike. some parts are from a 70 but i thing they adapt easily.

ill get a pic of that frame up soon as kiddo lays down for a nap.

 

[Amped]

I'd pick the lightest frame . Cuting weight is the easiest way to improve times. And you want to use a centrifugal clutch because you can achieve 100% lock up with centrifugal clutch, while a torque converter can only achieve 95% lock up. If you can aford it buy a BULLY. http://buller.net/cat--Bully-Clutches--clutches.html

 

[exenos]

I'm not going to get into the specifics, mainly because I don't know all the deatils, but you can achieve 99.999%(effectively 100%) lockup with a properly setup CVT system. You cant do it with something like a 30 or 40 series, but a full blown CVT system like a set of sled clutches can be setup to have a effective 100% lock with no belt slip. Its not good for the belt but it can be done.

Also at those bully prices.

 

[beansdaddy78]

wow that is an expensive clutch. no at the moment i wont be affording that one. its a stretch for me to try to buy a $100 1" clutch.