building shift gearing

meerkatt said:
just to get the revs up. most cag clutches dont kick in till 6k, racing clutches are often set to 8000rpm , thats where the ponies live. unlesss you run really light springs youll get nowhere and burn clutches at 3-5k
Click to expand...

Okay, so you mean a larger chain ring sprocket?

My GP460 engine originally came with 8,000rpm clutches, so I replaced the springs with 3,000rpm springs.

I have swapped in $9 CAG clutches onto my 460 engines. They are tapered-bore with keyway, velvet-smooth and seem to engage right off of idle(2500rpm). My 460 and Tanaka 47R clutches are brutal. Even with DDM lighter springs, I'm having major chattering issues. :-||

Now the complete Cag clutches are only $7!!!

http://www.davesmotors.com/s.nl/c.885035/n.1/it.A/id.3821/.f dance1
 
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Yesterday with a GPS on the bikes the blue cvt one with the 51cc big bore went 35.4 mph.
The in frame with stock motor went 36.5 mph.
A 50cc Chinese scooter went 36.2 mph

Ths scooter is more comfy, but not as much fun.

I want to look for weaker clutch springs, but where?
 
Thanks Dan. At those speeds they were all maxed out. Yes I felt nervous with out a leather jacket, helmet and gloves.
Had a pocket bike too that also maxed at 36mph. Did them all for baseline.
Even though the "in frame" is plenty fast enough, just gotta build a shift kit!?
Tried to stretch the springs before to lower the stall. With them uneven, Got some pulsating and chatter.
Google to the rescue.
 
I can't remember how well it worked but drilled 3 small holes in each of the weights of a clutch for a stage 3 Grubee GB. to try and stop pre-engagement. Just a thought.

(Google) I know!!! Was talking to some one recently who asked how I knew how to fix an oven after she had seen one of my better MB builds. Told her I didn't, Googled it. We could build a space shuttle given the $ (and wish to meet our makers, snork)

. Not only can you look up "how2" but can ask folks questions.
On NPR last Fri, they rebroadcast a show from 1993 about this new thing called the "internet" All the participators were online, not phone. One "caller" suggested that some day you be able to listen to music and if you liked it, download and buy. LOL, they discussed the copyright thing. One of the experts did say he was getting to much email. This was before Spam was invented
 
Thanks Dan, Yes the internet sure took over TV for me.

Did a little work yesterday: hooked up lights and battery on the cvt bike.

Between working on my car, managed to take off the old transmission and install the new one. It has a double chain drive and is smaller. The sprocket is close to the engine frame and may need notched for chain to jackshaft clearance.
Took some "shakey" videos trying to ride the bikes. Now to figure how to edit them and how to post them here??
 

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old motorbike said:
Took some "shakey" videos trying to ride the bikes. Now to figure how to edit them and how to post them here??
Click to expand...

While some use YouTube - Broadcast Yourself. - I don't like how they reformat (reduce file size & quality) and the time limit they've got, I prefer using Image hosting, free photo sharing & video sharing at Photobucket which, while they too reformat - it's not as bad as YouTube... *shrug* personal preference really lol ;)

In any case - both are free & quite simple to use and after you're done uploading will offer links to copy and paste in your post.

Lookin' forward to that actually, neat stuff man (^)


hmm... as far as "editing" vids - ya might wanna shoot http://motorbicycling.com/members/dave31/ a PM, he's made a ton of edited vids & he's quite good at it - but I dunno what he uses for an editor *shrug*
 
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You guys (BA and Dave) beat me to it. Both are really easy to learn and WMM has some cool little editing and effects. I put a link to some guy named "Fairracing" below. I make folks stocking stuffers from their family photo albums. I don't know what the Mac version is but if your Windows PC does not have it, is a freebee down load. Windows Live Movie Maker Teacher Guide

http://photobucket.com/

YouTube - fairracing31's Channel

Also, my sig was made with WMM.

LOL, way to much coffee today
 
Wow, Wish we had some open roads here like fairracing's area.
Open roads and no cars!!!! What a dream.
Great video.
Dan, your vid caught my eye.
Tomorrow morning, may attempt WMM
Today No job again, so worked on the bike some.
Found the jack shaft bearings and sprockets fitted together would fit in a 1-3/8 ID tubing. Cut and fitted everything then welded a 2" angle iron bracket to it and clamped it on the motor frame. Fitted chains on both sides. Started to drill bolt holes and ran out of time.
 

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Today after inventorying my leftover parts supply, there was a 43 or 4 tooth o5t sprocket destined for decreasing the gear ratio.

After drilling and attaching it to a sprocket with the proper spline, (hand ground in shaft) then a chain cut and a tensioner fabbed.
A lot of details needed attention for alignment.

Running again the ratios were perfect. Only 3 gears were changed and the bike chain flew off the front sprocket.
Taking out 2 teeth tightened the chain tension more.
After a few more shifts, off it went again.
I added the old tensioner from the old set-up to stabilize, and it jumped both the sprocket and tensioner.
Had a commitment and had to leave it for tomorrow.

This is my 3d month without a job and pay. Soc. Sec. is running thin so I may need to stop until work is found.
Maybe 1 more day?
 

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old motorbike said:
Today after inventorying my leftover parts supply, there was a 43 or 4 tooth o5t sprocket destined for decreasing the gear ratio.

After drilling and attaching it to a sprocket with the proper spline, (hand ground in shaft) then a chain cut and a tensioner fabbed.
A lot of details needed attention for alignment.

Running again the ratios were perfect. Only 3 gears were changed and the bike chain flew off the front sprocket.
Taking out 2 teeth tightened the chain tension more.
After a few more shifts, off it went again.
I added the old tensioner from the old set-up to stabilize, and it jumped both the sprocket and tensioner.
Had a commitment and had to leave it for tomorrow.

This is my 3d month without a job and pay. Soc. Sec. is running thin so I may need to stop until work is found.
Maybe 1 more day?
Click to expand...

Glad to see progress, OMB.

What exactly are your sprocket sizes and location? What size is your bike chainring sprocket?
 
The transmission is a 3.25:1, trans to jack shaft was 11:43, will be 11:33, gear to chain ring -10:40, then roughly 1:3 bike sprockets

Had it working with the 43 on jack shaft 2 nights ago. Geared just a little low.
Front bicycle chain jumps off. Used old chain tensioner to stabilize bottom of chain. Need to also have one on top.

Waiting for 33t sprocket for another try.

Had a job yesterday and today, So I have a reprieve this week.
 

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I had major chain jump for months on my bicycle chainring 22-tooth sprocket.I used the original front derailleur to keep the chain from jumping outward. Then I bought SBP's Jump-Stop to keep the chain from jumping inward. I still had chainjumping problems, until I replace the 22t with a 30t, moved the sprocket outward 1/4" and shortened the chain.

My chain jumps disappeared after that.

What is your ratio, not including the rear cassette?
 
old motorbike said:
The transmission is a 3.25:1, trans to jack shaft was 11:43, will be 11:33, gear to chain ring -10:40, then roughly 1:3 bike sprockets

Had it working with the 43 on jack shaft 2 nights ago. Geared just a little low.
Front bicycle chain jumps off. Used old chain tensioner to stabilize bottom of chain. Need to also have one on top.

Waiting for 33t sprocket for another try.

Had a job yesterday and today, So I have a reprieve this week.
Click to expand...

Let's try to calculate your gearing:

trans = 3.25:1.....
43t/11t = 3.91:1.....
40t/10t - 4:1.....

3.25 x 3.91 x 4 = 50.83:1...
33t/11t = 3:1.....
3.25 x 3 x 4 = 39:1.....

What is your bicycle chainring size?

If you use a 36t chainring for your bicycle chain, you should be fine. You might not need a belt tensioner with the 36t. The rear derailleur acts as a tensioner.
 
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Thanks 5-7HEAVEN, Your math seems excellent. I have a 10-40 tooth chainring from jackshaft and a 36? (will count it) front chainring on bike. I think the front de railer would keep the chain in place. I'll try to find one today.

Have a 33 tooth sprocket coming for the jack shaft to replace the 43. My splines I cut aren't the straightest so the 33 will mount to a smaller gear right to the 5/8" keyed shaft and bring the ratio perfect. Should get that Wed or Thurs.
 
chain jump! some walmarter mongooses i've ridden will jump in higher gears brand new, just casually riding. how rounded your teeth are will affect it. on most bikes you can swing the rear derailleur forward and tighten it up, wrapping the chain over more teeth, chain wear will affect it, chains wear and get slightly longer.
 

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