Two Stroke Mini Bike

[Desertduler]

Quick and easy but dont you need a big expensive machine to Hydroform?

The videos that I have seen they were using pressure washers as the hydraulic force.

 

[NewbCarter]

Thank you, when you ask about direct drive go kart engines what comes to my mind is a engine with just a sprocket on the output shaft and of course if you had a one way bearing inside just a drive sprocket you could bump start the kart and when the engine started the kart would never move but I think that you are just asking about the use of a one way bearing as I am using in a go kart application? If the clutch uses a needle bearing as an idler bearing then one could replace the bearing as I have with a one way bearing and be able to bump start the kart but if the engine being used has a way being started recoil, electric, etc this modification would be senseless unless one would want engine braking all the way down until the engine pto rpm over ran the clutch drum rpm. This bearing has nothing to do with the rating of the clutch capabilities, shoe contact surface and shoe contact force and shoe material have a factor on how much HP an centrifugal clutch will handle in the case of this clutch I have used this same clutch now on my Rotary Engine powered karts since I built them and they have been bullet proof but that was after I have modified them for my use, they hook up with out slipping both on and off asphalt. My Wife's Kart engine puts out some real good power and I have used the kart hard without having any clutch problems. Here is a photo of the modified clutch that I have used on this Rotary engine after it has been on my kart and used hard and now it is on her kart, notice that the clutch drum does not show any signs of heat discoloration due to slippage, that is because I have modified the clutch shoes to be able to pin down the power out put of these high hp engines which are at least 25 to 30 hp. This clutch in it's stock form could not handle the out put of any of these engines that I am using them on so their original rating goes out the window.

These engines are bump started , and yes by direct drive i meant that there is no clutch , only sprocket-chain-sprocket .

So it is possible , as long the clutch can be modified to accept the one-way bearing and it can handle(clutch) the engines output ?

 

[Desertduler]

These engines are bump started , and yes by direct drive i meant that there is no clutch , only sprocket-chain-sprocket .

So it is possible , as long the clutch can be modified to accept the one-way bearing and it can handle(clutch) the engines output ?

Yes,the reason that I am doing this is so this mini bike can be bump started not all of these one way bearings have steel springs in them to engage the needles some are plastic and they melt and distort when the bearing subject to high heat and then the one way bearing becomes inoperative. I use STP to lubricate these one way bearings because I have found that these types of bearings don't always work as they should when they are lubricated with some greases.

 

[Desertduler]

I took a two quart cooking pot and with a little help from my lathe I made a flywheel cover for this engine. I turned the inside of the pot so that it would fit tightly down on the machined surface where I machined the magneto side of the crankcase half down, then I drilled and tapped out four holes through the pot into the machined crankcase area and I mounted the cover down with four 6 X 1.00 mm socket headed screws.want to keep this engine as narrow as possible in order to do so I had to machine a hole in the cover as so that the flywheel snout would protrude through the hole and then I will cover and cap the snout off with a section of aluminum tubing as shown in the picture. ( Note: I used a pot with a non stick cooking surface)

 

[chancer]

That looks cool. And the non stick was definitely the way to go.

 

[2SlickNick]

Bret! You are a mad scientist! I love it!

---------- Post added at 10:57 PM ---------- Previous post was at 10:56 PM ----------

Now pot is medicinal, recreational,and mechanical...Lol.

 

[chancer]

Bret! You are a mad scientist! I love it .

Like Kelly Wood. "Mad Kartist" Use whatever is handy and works. I have seen Kelly use a Collander from his wifes kitchen! LOL
Must be a Utah thing.

 

[Desertduler]

Bret! You are a mad scientist! I love it!

---------- Post added at 10:57 PM ---------- Previous post was at 10:56 PM ----------

Now pot is medicinal, recreational,and mechanical...Lol.

Right on Nick! "Pot for Parts"

---------- Post added at 03:19 AM ---------- Previous post was at 03:10 AM ----------

Like Kelly Wood. "Mad Kartist" Use whatever is handy and works. I have seen Kelly use a Collander from his wifes kitchen! LOL
Must be a Utah thing.

Lol, maybe I don't know, this is the first time that I have had to search for something that I could make an engine part out of at the local Wal-Mart in the home living pots and pans isle with my 7 inch micrometer in hand measuring pots, but hey it was productive!

 

[itsid]

I love it..
it's just a perfect fit..

Looks like it was meant that way...

Not sure about the tube, I'd lean towards a strainer (stamped sheet, not mesh) maybe mounted on spacers...
- anyways - towards a dome shape instead of a cylinder

'sid

 

[Desertduler]

I love it..
it's just a perfect fit..

Looks like it was meant that way...

Not sure about the tube, I'd lean towards a strainer (stamped sheet, not mesh) maybe mounted on spacers...
- anyways - towards a dome shape instead of a cylinder

'sid

Yes I agree, I will find or make a dome kind of like a automotive axle bearing hub cap of sorts.

 

[Desertduler]

I cut down the stock engine mount and drilled and slotted the engine mount holes in my mill and I have tack welded the engine mount in the final location, a tight squeeze indeed but I made it work, I am now waiting for sprockets that I have bought to come in the mail so that I can start to build a jack shaft for the "Little Evil" as I will call it mini bike.

 

[itsid]

it's a shame they don't make those nice clean centerline rims in mini bike sizes

'sid

 

[chancer]

That looks good in there. The flat paint on the head matches the Pot. I am liking Sid's idea of no paint color. Just flat black and clear bare metal.

 

[Desertduler]

it's a shame they don't make those nice clean centerline rims in mini bike sizes

'sid

Good ol Centerlines, I love them, I had them on my race buggy and VW Thing, if they made them the size for this mini I would use them for sure!

---------- Post added at 05:59 AM ---------- Previous post was at 05:53 AM ----------

That looks good in there. The flat paint on the head matches the Pot. I am liking Sid's idea of no paint color. Just flat black and clear bare metal.

Yeah I kinda like it too, and with a flat black expansion chamber and blacked out wheels like I did on my Wife's kart the combo might look cool.
I have about twenty Tri Stars that I need to use up which I really don't care for the looks of that I may use, I have not decided yet.

 

[chancer]

Hey I wonder if those Hubcap things Kelly Wood made would, do you some good.

 

[Desertduler]

Hey I wonder if those Hubcap things Kelly Wood made would, do you some good.

With the Tri Stars that I have, I don't know how they would look, I might have to copy his idea somewhat and make some that look like the Centerline wheels that I like. Here is a photo of the type of Centerline wheels that I had on my VW Thing and my race buggy, of course I would not need the center hole large like the wheel has in the picture or the lug stud holes either.

 

[itsid]

With the Tri Stars that I have, I don't know how they would look, I might have to copy his idea somewhat and make some that look like the Centerline wheels that I like. Here is a photo of the type of Centerline wheels that I had on my VW Thing and my race buggy, of course I would not need the center hole large like the wheel has in the picture or the lug stud holes either.

For the Königskart (that poor backburner thing from back in the days)
I had Honda Monkey rims in mind ..(z50)
well or mooncaps... anyways

they're still a bit tall for a mini bike being 8" I guess, but maybe they do indeed fit.


3.5" wide -as mentioned 8" dia- and the ones depicted are made by G-Craft (several other companies make them as well)

but since you like centerlines as much as I do.. maybe that's at least something I should mention
and since that's Honda Monkey parts, no need to tell you there are matching front and rear hubs for a two wheel application, right

'sid

 

[Desertduler]

For the Königskart (that poor backburner thing from back in the days)
I had Honda Monkey rims in mind ..(z50)
well or mooncaps... anyways

they're still a bit tall for a mini bike being 8" I guess, but maybe they do indeed fit.

View attachment 68634
3.5" wide -as mentioned 8" dia- and the ones depicted are made by G-Craft (several other companies make them as well)

but since you like centerlines as much as I do.. maybe that's at least something I should mention
and since that's Honda Monkey parts, no need to tell you there are matching front and rear hubs for a two wheel application, right

'sid

Good information, Thank you!

 

[Desertduler]

Here are the jack shaft bearing mounts that I have made out of 1/4 thick flat bar material. I bored the bearing holes in my mill with the aid of my Criterion boring head, here is a photo of the mock up of the jack shaft I will locate where the sprockets need to be and then I will cut down the length of the shaft and mill keyway slots and drill and tap the ends of the shaft and make some custom retaining washers for the ends of the shaft.

 

[rocketkart]

the spark is going to shoot Through the seat and shock your gonads!!! lol jk nice build.