lazer line up for sprockets

[Tom MLC]

you are correct. gearing is constant. 15-42 in 630 is the same as 15-42 in 520.The sprogs are just a lot smaller but there ratio is the same.

What you do want to watch when converting down is the distance between your pivot and the chain. with the much smaller sprogs the chain can contact the pivot and grind out a nice trench. Especially if you upgrade your swingarm to something newer..15-42 won't work.

I run 17-47 on my kat which is a little taller than stock. The rule of thumb is for every tooth gained or lost on the front gain or lose 3 on the back.

I will be posting a gear ratio chart on my site soon.

Yes, I agree here. The gear ratio would remain the same without chainging the number of teeth. But the smaller sprockets might result in the chain hitting the swing arm. So going up 1 to 3 is recommended. I went from 15/42 to 17/48. Keeps me at a 2.8 gear ratio.

 

[Guest]

ahahahahh............... He is WRONGGGGGGGGGGGGGGGGGGGGGGGGGGGGGG!!

if YOU look at the cog. you will see on the engine side the bushing/spacer on the shaft pases through the "spacer/dampening on sprocket" and contacts directly with the sprocket.

Put another way.... if you remover the dampening crap from the stock sprog it will sit in the same spot.

The 530 sprog is only thinner from the inner face out. It WILL NOT sit closer to the engine than the stock one..Tom.. believe me. The 530 sprog will sit exactly as close to the engine as the 630 cuzzzzzz the bushing on the shaft passes through the dampening and spaces the sprocket only. The dampening sits OVER the bushing/spacer.

 

[Guest]

the red box is the 18.50 bush/spacer. This is a suzuki pic of the 78 1000 front sprocket and shaft. Notice the sprog is flat.
I don't care how thin a sprocket you put on here, it can not and will not and does not nor can it get any closer to the engine cases than any other flat sprocket or the stock sprocket.

The only limitation comes in with the nut. it has a limited range and may need a spacer between it and the OUTSIDE of the sprocket so it will tighten down properly.

WHEEEEEEEEEWWWWWWWWWWWWWW... I am tired. Can I get an Amen?

 

[Guest]

And Tom,

You bikes look nice man.... Very clean...

 

[Tom MLC]

Okay Rob, I give up!

I know you are far more experienced than I. Truely. I'm not being sarcastic. And I have always come to trust the Guru's here on the GSR...mostly. I know you wouldn't lead me wrong. At least not deliberately.

So one Rob is right...and one is wrong.

My new sprocket is coming back off. I'm gonna take a closer look at this thing.

Thanks. Oh, by the way...nice tool!

 

[80GS1000]

Yes, I agree here. The gear ratio would remain the same without chainging the number of teeth. But the smaller sprockets might result in the chain hitting the swing arm. So going up 1 to 3 is recommended. I went from 15/42 to 17/48. Keeps me at a 2.8 gear ratio.

Maybe I'm just dense, but wouldn't a 15 tooth 530 front sprocket be the same diameter as a 17 tooth front sprocket, same as a 42 tooth 530 rear sprocket be the same diameter as a 47? How would adding more teeth to the sprockets keep the chain from hitting the swingarm?

Will probably be making small chain runners to be attached on both sides of the pivot area of the swingarm out small strips of UMHW tape to keep from transforming the bike into an overpowered chainsaw. A whole lot cheaper to replace the plastic as needed compared to the swingarm.

 

[denydog]

I don't care how thin a sprocket you put on here, it can not and will not and does not nor can it get any closer to the engine cases than any other flat sprocket or the stock sprocket.

The only limitation comes in with the nut. it has a limited range and may need a spacer between it and the OUTSIDE of the sprocket so it will tighten down properly.

WHEEEEEEEEEWWWWWWWWWWWWWW... I am tired. Can I get an Amen?

Yes, It's so clear now!!!! Well done! Good job!

That's why I mounted my sprocked this time with the raised portion outside away from the motor. And another example of why not to trust a motorcycle shop to get it right!

 

[Tom MLC]

Rob, if I could make one of these smilies Kow-Tow...

Here's my front sprocket, minus the 6mm spacer pushed up against your 18.50mm bushing. Seems to be plenty of clearance.

Lots of extra shaft spline this way. I need that 6mm spacer here.

And there it is...

Here's the lock washer

Now where's that nut???
...

 

[Tom MLC]

...
Oh, there it is!

And hey, give a listen.

Now it's not torqued down yet, and this doesn't confirm alignment...but I don't hear any rubbing. I think its a winner!

Rob, you have my permission to slap this 'ol Irishman right in the thick spot...anytime. I owe ya one, dude!

 

[Guest]

Now you got it brother. Your chain and sprogs will thank you. you will also have a much smoother cruise on the hwy cuz that much missalignment will cause a real drone on the hwy that will make it quite unpleasant to ride.

Glad its all sorted out dude. Good ridin'

 

[Guest]

your alignment is now true but check the rear axle? it could be ascew which brings us back to my wonderful little tool....

and as always... you are most welcome..

 

[Guest]

Maybe I'm just dense, but wouldn't a 15 tooth 530 front sprocket be the same diameter as a 17 tooth front sprocket, same as a 42 tooth 530 rear sprocket be the same diameter as a 47? How would adding more teeth to the sprockets keep the chain from hitting the swingarm?

Will probably be making small chain runners to be attached on both sides of the pivot area of the swingarm out small strips of UMHW tape to keep from transforming the bike into an overpowered chainsaw. A whole lot cheaper to replace the plastic as needed compared to the swingarm.

MOre teeth larger diameter=greater chain height. 17/48 keeps the chain about the same height above the pivot as the stock 15/42.

look at the two sprockets I posted. Left=15t Right=17T and still the 17 is a little smaller. 15 teeth 3/4" spacing is longer than 15t with 5/8 spacing. That makes a smaller cog. Which like going from a 19" front wheel to a 17" front you lose an inch of height..right! because the diameter is smaller. That drops your chain height too and brings it closer to the pivot. The smaller rear sprocket compounds things and more drop of chain height.

 

[80GS1000]

MOre teeth larger diameter=greater chain height. 17/48 keeps the chain about the same height above the pivot as the stock 15/42.

look at the two sprockets I posted. Left=15t Right=17T and still the 17 is a little smaller. 15 teeth 3/4" spacing is longer than 15t with 5/8 spacing. That makes a smaller cog. Which like going from a 19" front wheel to a 17" front you lose an inch of height..right! because the diameter is smaller. That drops your chain height too and brings it closer to the pivot. The smaller rear sprocket compounds things and more drop of chain height.

Thanks for the clarification. Looks like an exchange to 17/48 is in order for those 15/42 sprockets that are on order.

 

[Guest]

Thanks for the clarification. Looks like an exchange to 17/48 is in order for those 15/42 sprockets that are on order.

what yr swing and rear wheel are you using?

did the swing fit or did you have to mod the frame?

Give me an email dude. stunts@telus.net

 

[KEITH KRAUSE]

katman, thanks a lot for taking the time to 100% prove what needs to be done. I sense a bunch of people have installed that spacer wrongly and they'll be wearing out chains and sprockets very quickly or even worse.
A few days ago chef started a related thread "Sunstar sprocket" that Tom replied to. My first reply was that the spacer shouldn't be used. But without wanting to take my bike apart to look at things, I soon got swayed into believing the spacer was needed too. Everyone was so sure of themselves. It still seemed wrong though but I figured I'd just wait and see for myself if I ever do the conversion. Some trusted sources that people here believe in turned out to be wrong.
I hope the word gets out so everyone who has done the conversion can make it right. This is a potentially serious mistake. The chain could break and cause damage, not to mention an accident. At the least, you'll wear out these expensive sprockets and chains very quickly.
You really have to be careful when changing things from stock. It's easy to believe in a source because they have a website or they've been in business for years or whatever. This is a great example.
katman, thanks again for taking the time to sort this out. You've saved a lot of people some trouble.
I think that those that have done the conversion should contact their supplier and inform them that they need to change the installation instructions for some models.