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Author Topic: What sprocket size you running? CB750  (Read 5473 times)

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Offline brandEn

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What sprocket size you running? CB750
« on: May 15, 2011, 05:24:47 PM »
At the risk of getting flamed I am asking... What size sprockets/gearing you using?

After a few miles on my new build I am thinking the 17T front 48T rear with 630 chain is in need of a change. I don't anticipate much slab time with this bike so I am thinking about changing sprockets size for a bit more pep. Thoughts? Input?
« Last Edit: May 15, 2011, 05:36:46 PM by brandEn »

Offline Gordon

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Re: What sprocket size you running? CB750
« Reply #1 on: May 15, 2011, 05:28:06 PM »
Going with a smaller rear sprocket will do the opposite of giving the bike more "pep".  You either need a smaller front sprocket or larger rear (or a combination of both) to increase the low-end torque.

Offline brandEn

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Re: What sprocket size you running? CB750
« Reply #2 on: May 15, 2011, 05:31:07 PM »
Ah, thanks for the clarification. Now that I think about it that makes sense. Thats why those stunt bikes have those huge rear sprockets.

fixed...
« Last Edit: May 15, 2011, 05:37:13 PM by brandEn »

Offline tweakin

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Re: What sprocket size you running? CB750
« Reply #3 on: May 15, 2011, 06:01:16 PM »
Dude,  Why don't you at least get more than 50 miles on the thing before you think about changing the gearing.  J/K,  ;D

edit: you are worse than me...
At the risk of getting flamed I am asking... What size sprockets/gearing you using?

After a few miles on my new build I am thinking the 17T front 48T rear with 630 chain is in need of a change. I don't anticipate much slab time with this bike so I am thinking about changing sprockets size for a bit more pep. Thoughts? Input?
« Last Edit: May 15, 2011, 06:03:09 PM by tweakin »

Offline brandEn

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Re: What sprocket size you running? CB750
« Reply #4 on: May 15, 2011, 06:08:18 PM »
haha, 50 miles? How bout 79.3! Yea get some!

Offline brandEn

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Re: What sprocket size you running? CB750
« Reply #5 on: May 15, 2011, 06:09:05 PM »
 And by the way...nobody is worse than you!
 ;D

Offline wookie

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Re: What sprocket size you running? CB750
« Reply #6 on: May 15, 2011, 07:22:17 PM »
Break your motor in, get it tuned properly and then think about gearing.  I run a 17/48 520 with no complaints.

J

Offline Don R

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Re: What sprocket size you running? CB750
« Reply #7 on: May 15, 2011, 08:26:12 PM »
Way back in the olden days we used a 17 on the front for performance, sometimes with a 50 rear then an 18 / 48 for highway use. If we were pushing a windjammer or a lot of weight we left the 17 on all the time
The wheel keeps on turning and you cant slow down, you can't hold on and you can't let go, you can't go back and you can't stand still, if the thunder don't get ya then the lightnin will.

Offline MCRider

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Re: What sprocket size you running? CB750
« Reply #8 on: May 15, 2011, 08:26:13 PM »
The 17/48 combo is usually with a 530 chain. The increase in size to a 630 drops the number of sprocket teeth front and rear. Sure we're talking about the same thing?

In my opinion 17/48 is the best al around compromise, as the stock setup was 18/48. You could go to a 16/48 but you'd be turning alot of revs at highway speeds. Increasing the rear may foul the chainguard, if you're running one.

Wookie: I didn't know there was a 520 conversion either. Sources?
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Offline brandEn

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Re: Re: What sprocket size you running? CB750
« Reply #9 on: May 15, 2011, 10:46:01 PM »
The 17/48 combo is usually with a 530 chain. The increase in size to a 630 drops the number of sprocket teeth front and rear. Sure we're talking about the same thing?

In my opinion 17/48 is the best al around compromise, as the stock setup was 18/48. You could go to a 16/48 but you'd be turning alot of revs at highway speeds. Increasing the rear may foul the chainguard, if you're running one.

Wookie: I didn't know there was a 520 conversion either. Sources?

Thanks for the input. Yes I am running JT sprockets 17 up front and 48 rear with a 630 DID chain. What ratio is that comparable to with a 530 chain?

Offline MCRider

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Re: What sprocket size you running? CB750
« Reply #10 on: May 16, 2011, 04:41:56 AM »
If in fact you have a 17/48, its the same ratio as any other 17/48. The chain size doesn't change the ratio. But your sig says its a 78 750F and they came with a 14/43 using a 630 chain, which is "more power" than a 17/48 ratio.
« Last Edit: May 16, 2011, 04:44:55 AM by MCRider »
Ride Safe:
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1988 NT650 HawkGT;  1978 CB400 Hawk;  1975 CB750F -Free Bird; 1968 CB77 Super Hawk -Ticker;  Phaedrus 1972 CB750K2- Build Thread
Youth and Talent are no match for Age and Treachery.

Offline wookie

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Re: What sprocket size you running? CB750
« Reply #11 on: May 16, 2011, 06:27:37 PM »
The 17/48 combo is usually with a 530 chain. The increase in size to a 630 drops the number of sprocket teeth front and rear. Sure we're talking about the same thing?

In my opinion 17/48 is the best al around compromise, as the stock setup was 18/48. You could go to a 16/48 but you'd be turning alot of revs at highway speeds. Increasing the rear may foul the chainguard, if you're running one.

Wookie: I didn't know there was a 520 conversion either. Sources?


Yeah, it was something that cycle x offered at one time.  O-ring chain, decent quality, so far so good.

J

Offline MCRider

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Re: What sprocket size you running? CB750
« Reply #12 on: May 16, 2011, 06:36:14 PM »
SNIP
Wookie: I didn't know there was a 520 conversion either. Sources?


Yeah, it was something that cycle x offered at one time.  O-ring chain, decent quality, so far so good.

J

Cool. No reason a modern 520 can't be used. Such a conversion is hot setup on HawkGTs (I have one) and many make a lot more hp than our CBs ever will.  Much lighter.
Ride Safe:
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1988 NT650 HawkGT;  1978 CB400 Hawk;  1975 CB750F -Free Bird; 1968 CB77 Super Hawk -Ticker;  Phaedrus 1972 CB750K2- Build Thread
Youth and Talent are no match for Age and Treachery.

Offline TaylorG

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Re: What sprocket size you running? CB750
« Reply #13 on: May 28, 2011, 11:58:34 AM »
Hmm, I got my 750f running and replaced the rear sprocket and chain with what I thought was the stock sprocket combo: 14/43 630 chain.  I road tested the bike and gearing seems way off.  I'm in second before I'm out of first and at 60, the RPM's are screaming!  Should I look at a new gearing combo?  17/48?  Or do I have another problem?  With the exception of a leaky carb, bike starts, runs and sounds great.  Any thoughts from the forum would be really appreciated. 

Online 754

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Re: What sprocket size you running? CB750
« Reply #14 on: May 28, 2011, 01:04:15 PM »
 I am sure its 530 chain, if you have 17/48

 17 /54 is fun on the street, just change to 19 for longer distances..

 Any 530 can be switched to 520, just thin the sprockets..
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Offline Spanner 1

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Re: What sprocket size you running? CB750
« Reply #15 on: May 28, 2011, 02:58:28 PM »
17/48 K1 750 @ 60 mph 5th. gear = exactly 4,000 rpms....... nice :) ;D

Offline Tripps

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Re: What sprocket size you running? CB750
« Reply #16 on: May 28, 2011, 06:24:57 PM »
?Stock?  78 750K, 4200 at 60 mph.
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Offline Spiider

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Re: What sprocket size you running? CB750
« Reply #17 on: May 28, 2011, 06:29:21 PM »
17/48 with a 530 chain.

 

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