Bonanza BC-1300 Jackshaft Information & Parts List Needed ~show me your jackshafts ;D

[KustomKartKid]

Yeah the sprocket should have it own set screw(s). Usually one directly over the key and another 90* away. The key carries all the load, the set screw just keeps it from sliding back and forth.

Put a drop of Loctite on the set screws or put another set screw on top to keep them from vibrating loose.



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[OND]

I don't have a jackshaft ! :laugh:

 

[gumpit]

I didn't pay much attention to it before I cut it off. But it was bent.

 

[manchester1]

Any minute now, somebody will post one of those gear ratio charts that I don't understand:laugh:

 

[MoTo-BunnY]

I didn't pay much attention to it before I cut it off. But it was bent.

Awesome, thanks. . . .the proverbial pictures say a thousand words....

 

[MoTo-BunnY]

Any minute now, somebody will post one of those gear ratio charts that I don't understand:laugh:

lol, I know what you saying!

 

[KustomKartKid]

Burris Racing Jackshaft Calculator

So plug in the numers you have for example: engine clutch 12T, jack input 15, jack output 13t, rear sprocket 60t....

On a bike like that, you typically want something in the neighborhood of 6:1 final drive ratio for a 4 stroke 3-5 HP.



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[MoTo-BunnY]

Burris Racing Jackshaft Calculator

So plug in the numers you have for example: engine clutch 12T, jack input 15, jack output 13t, rear sprocket 60t....

You typically want something in the neighborhood of 6:1 final drive ratio for a 4 stroke 3-5 HP.....



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Cool! that's a neat calculator thingy! thank you very much......I might actually be able to figure it out then, even being as math-challenged as I am.....

 

[manchester1]

:laugh::laugh: I knew the chart would show up:laugh: All my bikes I run a 12T clutch,
14T sprocket from the clutch to jackshaft. 60T rear sprocket and 11T sprocket to jackshaft. Seems to work great with all different horse power engines:shrug:

 

[OND]

:laugh::laugh: I knew the chart would show up:laugh: All my bikes I run a 12T clutch,
14T sprocket from the clutch to jackshaft. 60T rear sprocket and 11T sprocket to jackshaft. Seems to work great with all different horse power engines:shrug:

:laugh::laugh::laugh:

 

[MoTo-BunnY]

Burris Racing Jackshaft Calculator

So plug in the numers you have for example: engine clutch 12T, jack input 15, jack output 13t, rear sprocket 60t....

You typically want something in the neighborhood of 6:1 final drive ratio for a 4 stroke 3-5 HP.....



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OK, looks like I am good for parts there other than the need for new sprockets that actually have set screws in them. Seriously on the two 13 tooth jack-shaft sprockets that came on mine, one has NO set screw hole at all and the other has just one?!? this is a weird bike.....

I just checked my clutch stash and I have both 11 & 12 tooth clutches and my rear most sprocket has 72 teeth. Using an 11 tooth clutch, the ratio would be 6.55 to 1 and with the 12 tooth, 6.0 to 1. :thumbsup: whoo hoo! Even a non-math (differently abled?) minded gal like me can figure it out, using that calculator thingy. :thumbsup:

 

[manchester1]

Did you say that one of your jackshaft sprockets had a bolt in thereut: Those jackshaft sprokets kinda look like the original sprockets on my MX bonanza.

 

[MoTo-BunnY]

Did you say that one of your jackshaft sprockets had a bolt in thereut: Those jackshaft sprokets kinda look like the original sprockets on my MX bonanza.

Yep, no set screw just a small BRASS bolt jammed in there, not even the right thread pitch... :doah:

 

[KustomKartKid]

Kids did a alot of crazy stuff to get thier bikes going again especially if they had no other resources.

Looks in this picture like the side plates of the chain were rubbing on the edge of the spacer because the o.d. is too big. They would have been better off running the spacer on the outside...or flipping the sprocket around. If you're not going to use a shaft that is the proper length with snap ring grooves, then you need to run those lock collars somehwere...inside or out. Inside might look better but you need to make sure they are not interfering with anything.


Go with the 6.55-1 it will give you slightly less top end but more zip off the line

 

[MoTo-BunnY]

Kids did a alot of crazy stuff to get thier bikes going again especially if they had no other resources.

Looks in this picture like the side plates of the chain were rubbing on the edge of the spacer because the o.d. is too big. They would have been better off running the spacer on the outside...or flipping the sprocket around. If you're not going to use a shaft that is the proper length with snap ring grooves, then you need to run those lock collars somehwere...inside or out. Inside might look better but you need to make sure they are not interfering with anything.


Go with the 6.55-1 it will give you slightly less top end but more zip off the line

Yeah, there are so many cobble job repairs on this thing that I assumed most of it was a kid improvising repairs to get their ride going again. I think this bike had a short, very hard life as it looks like it still has the original tires (and the front is still halfway good). It also appears to have sat outside in the rain for some time. :doah:

Thanks with the gearing suggestions, I was wondering what the difference would be between the 6.55 and the 6 to 1 ratios. :thumbsup: Going with the 6.55 gearing then, low end is definitely the focus on this build.


I'm preparing an order for OMBW to get the necessary hardware to redo this mess-a big thanks to everyone else with their suggestions and pictures! Also, Karen, your bikes are all soooooo nice! I can't believe that Taco setup, looks like industrial art to my eyes it's so pretty. :laugh: