FINALLY got one!!

[OzFab]

I don't know nothing about how collectible they are..

So, what do you know?

Sorry, couldn't resist that one... & your grammar is usually impeccable...

 

[firemanjim]

There's a Rupp website that sells repo 2 speed. I reverse engineered a 2 speed jackshaft mount for those Sears Ropers for a guy on OMB. Still have one left.

http://www.oldminibikes.com/forum/general-minibike-talk/81946-sears-roper-2-speed-jackshaft-box.html

http://blackwidowmotorsports.net/_13132r_two_speed_transmission_kit_68_69.html

http://blackwidowmotorsports.net/_713845_universal_comet_2_speed_clutch_kit_.html

Ryan, that guy won't say whether or not he has any ready for sale. I been trying to put one in the basket but it won't let me. And he won't return my emails about when s it ready .... SO...... I bought the NOS 2 speed jackshaft set upon eBay. Now I just need the double sprocket engine clutch. That's $80 at BMI.....
I have already read that thread. AWESOME work on the plate! So, whatcha want for the one you still have? Send me a pm please.... Probably PayPal you tonight..... So send the email too....
Robert, hold on to those parts. Especially the brackets. You can use a new tc but set it u old school style , for looks..... I love the sissy bar on yours. Mine has caps on the end tubes..... Gonna have to make me some like yours.....

 

[porsche930dude]

Have you tried a clone in there? I dont think itll fit with the jackshaft mounted high like that. Maybe not at all with the bars coming up

 

[firemanjim]

Have you tried a clone in there? I dont think itll fit with the jackshaft mounted high like that. Maybe not at all with the bars coming up

Not sure.... It should. Gonna remove the Predator tank anyway. Hopefully Ryan found the bracket he made. I got the 2 speed in today. Like a dummy though, I took it home at lunch before taking a pic of it. I'll post that up tonight. I'll measure the Predator on my daughters kart and check it against the Roper frame. I'm also considering using a 2 stroke 3hp Tecumseh engine. Eventually, I'll find a good period correct engine.
Speaking of the 2 speed..... Let me see if I understand this correct..... I have a twin 12 on the engine. 1st gear ratio is 12-24-14-48= 28mph and second gear will give me 12-12-14-48=57mph
All this is at 5400rpm on a 12" tire..... Does that math sound right? If so, I'm digging it.......
Got a quote to powder coated the frame and all, for $350 and $150 to media blast it.... Too much? I want a sunburst orange......

 

[firemanjim]

Not the best quality pics, but pics none the less..... If you guys want, I'll post a video later, explaining how this works, using the one-way bearing. I can't wait to get the clutch and bracket. This is gonna be cool!

 

[rmm727]

I found the bracket. Gotta bend that one tab. You got a nice looking 2 speed there. I've had mine (NOS as well) for about 4 years now. Never put it on anything. Just got the 2 sprocket clutch last year. Certainly is fun to hold in your hands and turn the first gear sprocket back and forth.

Now you need to get the 2.5 in band brake puck (and brake band) that goes on there as well. MAC on OMB has many. He was on this site as well.

 

[firemanjim]

Ryan, mine has the scrub brake. Was gonna keep that..... Is that gonna be a problem?

 

[landuse]

That really is one nice looking bit of kit.

 

[rmm727]

Ryan, mine has the scrub brake. Was gonna keep that..... Is that gonna be a problem?

No, I don't believe so.

 

[firemanjim]

That's good to know. I really like the scrub brake. People talk smack about them but I think they work good, and it keeps things as was.... Simple ,wheeled, motorized vehicle's.....
Getting really excited abut this. So glad I didn't just sell it. This is gonna be fun......

 

[firemanjim]

would ya?

Got the new bracket for the 2 speed! Thanks RMM727! !
Question.......
I bought a 2 stroke 3.5hp tec engine. Just to have , initially.... But now that its here, I was thinking..... Would you put it on this mini bike? I think the 2 stroke sound would be cool as heck
What do y'all think? I'd get rmm727 to build me a new engine mounting bracket to mount to the engine, and allow me to install it like a typical engine. The engine has a 5\8" keyed crank.
So would ya??

 

[2SlickNick]

I am thinking a grown man needs a bigger engine.

 

[rmm727]

Post up a picture of your engine. I may have the mount already designed as a 2 pc mount. In other words, a flat plate with the standard engine base pattern and a vertical plate with the pattern on the side of the engine. Just never took the time to figure out where it needed welded. Wanted to make a 1 pc mount as a member on OMB needed one copied but I think he found another mount so that idea fell thru.

Not sure how that motor will run but I want to aleast try mine on something.

 

[firemanjim]

Yeah Ryan, I know exactly what you're talking about! Gonna see how much room I have in there, for that engine. Then I'll see if the bracket like you're talking about will be feasible. I'm pretty sure it s though. It was what I already had in mind to begin with.
As far as the engine goes, I heard a "story" today from a truck driver picking up a load. He was there when my engine came in. He told me ,.........
"Son, I had a motor like that on a Thunderbird mini. We hot rodded the motor to around 8hp and had a good 'fat to skinny' exhaust that really pulled the power of that little sucker. And with the high RPM's, I could ride 50mph all day long...... "
Hmmm .... 8 HP out of a 3.5? I doubt it...... 5-6+ maybe..... High RPM's? It ain't spinning 10,000 rpm .......
So what COULD be pulled out of this little thing? Can you make a high performance expansion chamber type exhaust for the and get more out of it? Or is a straight pipe all that is needed? I've never messed with a little 2 stroke like this, so I'm at a loss. I know all the high output 2 strokes run the chambered exhaust, and gain a lot of power.
Maybe I should start a thread in the engine section, to see what kind of help I can get....

 

[2SlickNick]

You know Jim... I am now thinking you should go with the 2 stroke. I have owned many 2 stroke quads and dirt bikes and there is nothing better than the brapppp brappp Brrraaapppp sound. With proper gearing ( you already have the two speed) and a fatty pipe no reason you can't have an awesome; not your normal- run of the mill minibike.


As much as I love this site there is some very helpful and focused info at OMB for both your bike and engine.

I joined there too. Just make sure you share here....lol

 

[firemanjim]

Yep, Nick, I joined there too. I just bought a rear wheel assembly for my mini ,from ironhonky..... And at a great price.
I'm really liking the the 2 stroke idea.....

 

[2SlickNick]

Cool... I will search for you there. I have bought and sold at least 10 times on there too...

 

[firemanjim]

Cool... I will search for you there. I have bought and sold at least 10 times on there too...

You know my name.... LOL
It was too dark to take any pics, but last night I put on the old wheel assembly for the rear, and placed the 2 speed set up in its spot, for my viewing pleasure....
Its coming together, parts wise, nicely. Now I need a gas cap and a twist throttle set. Need to mount an engine..... Still deciding......
Will post some pics after work.

 

[bucci]

Wow you guys are blowing my mind with all this stuff.

 

[firemanjim]

Wow you guys are blowing my mind with all this stuff.

With the cool projects? With the parts we come up with? Or the "science" behind it all?.......