2 spd jack shaft doesn't look right

[SimpleTom]

This is on ebay.
Rupp Mini Bike Clutch and 2-Speed Jackshaft Assy. (NEW) | eBay

To me it looks like a normal clutch mounted on the jack shaft. The sprocket should be mounted to the clutch pad side and not the bell side. It should look like this Comet one.

Am I right??? :shrug: It's never going to engage.

 

[creia]

SimpleTom,
You are exactly correct.:thumbsup: I see that it has (now) sold- Somebody is going to be disappointed!:doah:
Michael

 

[KustomKartKid]

the gear on the outsdside with the heavy hub has (or should have) special needle bearings that act as a one way sprag...it will drive off of that until the clutch next to it reaches speed at which point it engages and overtakes the sprag causing it to disenagage and drive off the smaller sprocket on the clutch.....no???

 

[creia]

Kustom Kart,
You are ALSO exactly correct!:thumbsup: (no surprise).
The large sprocket should be part of the "sprag" (one way and ratcheting) clutch. It looks like the Ebay ad shows only a regular jack shaft sprocket installed!ut:
I wonder who bought it? If it was an OldMiniBikes member, no doubt we will see them posting it soon with questions?!

 

[KustomKartKid]

Kustom Kart,
You are ALSO exactly correct!:thumbsup:

Does that mean I have to share the prize??!!

...wait , what is the prize anyway........:laugh:

 

[pdlsa10]

I made the reproduction Rupp 2-speed clutches (like the one listed above) They are correct in every way and work perfect. The only difference from the original ones is that it uses modern internal clutch parts, there will be no disappointments. If you want to use the incorrect clutch, buy a cheaper Comet.

 

[pdlsa10]

#13132R TWO SPEED TRANSMISSION KIT, 68-69

 

[Scottyace]

Its correct the way it is. I was just there on my TT project. You can't see the one-way bearing in the first gear sprocket. Nice setup.

 

[pdlsa10]

http://www.oldminibikes.com/forum/mini-bike-parts/47746-rupp-2-speed-clutches-exact-copys.html

 

[Scottyace]

Kustom Kart,
You are ALSO exactly correct!:thumbsup: (no surprise).
The large sprocket should be part of the "sprag" (one way and ratcheting) clutch. It looks like the Ebay ad shows only a regular jack shaft sprocket installed!ut:
I wonder who bought it? If it was an OldMiniBikes member, no doubt we will see them posting it soon with questions?!

It does'nt ratchet, it free spins when jackshaft clutch engages!
It is correct, if it has the one way bearing in the first gear.
The only way to tell is if it is in your hand and first gear free spins one way, turns the jackshaft the other way.
Looks correct to me!

 

[KustomKartKid]

Like I said...it's called a "sprag"....still waiting on my prize....:glare:

 

[SimpleTom]

Okay, I know about the one way bearing in the first sprocket, but the engine will drive that sprocket until it reaches a certain RPM when the clutch pads on the jack shaft clutch would engage and drive the outer bell which is attached to the jackshaft. How does the jack shaft clutch engage on the one I posted on ebay??? What I see is that the two speed clutch drives the one way bearing sprocket and the bell on the clutch on the jack shaft, when and how does the bell engage the clutch pads on the clutch on the jack shaft???? :shrug:

 

[KustomKartKid]

.... What I see is that the two speed clutch drives the one way bearing sprocket and the bell on the clutch on the jack shaft, when and how does the bell engage the clutch pads on the clutch on the jack shaft???? :shrug:

you are correct Tom, but the bell is basically freewheeling on the jackshaft until the sprag clutch gets the jackshaft up to speed and the shoes engage the bell...at that point the bell "overtakes" the sprag becuase of it's sprocket size and then the bell is driving the jacksahft and the sprag goes into freeweel......

hell I'm confusing myself now..:doah:

 

[SimpleTom]

you are correct Tom, but the bell is basically freewheeling on the jackshaft until the sprag clutch gets the jackshaft up to speed and the shoes engage the bell...at that point the bell "overtakes" the sprag becuase of it's sprocket size and then the bell is driving the jacksahft and the sprag goes into freeweel......

hell I'm confusing myself now..:doah:

No, I get it now. To me the Rupp style would be a little more jerky when it "shifts" into high gear.

 

[creia]

If (and that is a BIG "IF") pdlsa10's 2-speed unit indeed performs like he is claiming, I stand corrected in my critique, and I learned something new today....:shrug:
Michael

 

[creia]

"...it looks different from its Comet counterpart..."
Yes, it certainly does! The Ruppster 86 and I are quite familiar with the Comet version on his Sears Roper, which has good performance. I would be very interested in how this "new" version performs as compared to the "old" Comet version. Has anybody actually compared the two, side by side?
Michael

 

[Adrenaline]

So my understanding from this and the thread from pdlsa10 linked is thereis still a clutch on the engine, and the 1st gear is always engaged from the jackshaft to your rear axle. Then when the jackshaft is up to speed 2nd gear engages and first gear freewheels. Please correct if I'm wrong.

 

[jeep2003]

so it can work with a normal clutch on the jackshaft is the real question ?. if i had a double sprocket clutch and a one way sprocket i could make one?

 

[KustomKartKid]

so it can work with a normal clutch on the jackshaft is the real question ?. if i had a double sprocket clutch and a one way sprocket i could make one?

yep...the "special" clutch in this case is the one on the engine...twin sprocket.

the jackshaft clutch is a regular clutch...the trick is finding the engine clutch and the sprag clutch...

 

[creia]

This is turning into an interesting and educational thread.:thumbsup: I would encourage and welcome any OldMiniBikes members who have one of these "new version" ("pdsla10") 2-speed units on their bike to provide us with a testimonial as to the performance, likes, dislikes, etc... ESPECIALLY if they have also had the "old version" ("Comet") 2- speed as well, to compare it to.
Michael