Author Topic: 520 or 530 chain/sprockets for a cb750 based road racer? (Read 5261 times)

gschuld · « **on:** August 01, 2015, 05:48:41 PM »

I'm interesting in hearing thoughts regarding using a 520 chain/sprocket setup for a road racer rather than a 530 set. I'd probably be looking to use 17/48(tighter tracks) to start with 17/46 for the faster tracks, and I plan to use the factory K drum rear hub.

Locating 530 sprockets is a an easy task. I am not seeing a whole bunch regarding 520 sprockets though, but enough to get me started. I have found 17 steel front and 48 aluminum rear sprockets at cognitomoto.com http://cognitomoto.com/collections/engine and 18/19 front and 46 chrome rear at CycleX. http://www.cyclexchange.net/Chain%20Sprocket%20Page.htm

Moto-madness carries a sprocket/chain set in 16/17/18 front and 48/49/50 rear sprockets http://www.moto-madness.com/Cafe-racer-caferacer-69-76-cb750-520-sprocket-chain-conversion-kit-honda-ahmra.html

Are any road racers out there running 520 chain? 520 chain has handled much more powerful motors, so I assume that it can handle a strong big bore cb750 with ease. Any recommendations regarding 520 conversion suppliers?

George

bwaller · « **Reply #1 on:** August 01, 2015, 06:52:00 PM »

I use anodized alum. rear sprockets from Sprocket Specialists. They've always been really quick getting them to me. I originally bought 520 fronts from JT Sprockets with a wider center section to ride on the c-shaft. These seem to be harder to find. Machined a few stockers narrower if you can stand the "singing".

I'm all over 520 chains, but investigate for best tensile strength. You're right a 520 is chain enough.

simon#42 · « **Reply #2 on:** August 02, 2015, 12:56:27 AM »

cant help with suppliers im afraid but i would go with a 520 every time , a good one will take more than twice as much power as you are likely to throw at it .

have found EK chains to be the best on a race bike , next to no initial stretch and then very consistent .

bwaller · « **Reply #3 on:** August 02, 2015, 04:42:09 AM »

I use EK too George.

gschuld · « **Reply #4 on:** August 02, 2015, 05:54:11 AM »

Brent and Scott,

Thanks for the info. I looked up the chains available in the EK Chain catalog and of the 3 strongest 520 rated chains, only one was recommended for road race applications, the MVXC series. It that what you guys are using?

http://www.ekchain.jp/product/catalog.html

I looked up the front sprockets on the JT sprockets website catalog and I seemed to find only sprockets cut for 530 chain. Am I missing something? I'd rather not turn down (thin) a brand new steel sprocket in the lathe without a compelling reason. I do like the idea of the thicker center section though.

http://www.jtsprockets.com/catalogue/model/5015
http://www.jtsprockets.com/catalogue#search-results

Rear sprockets: I checked in with the Sprocket Specialties website and found the rear sprocket page for the 70-76 cb750. Lots of options: The anodized option(matte black only) appears to be rear sprockets made from pre-anodized stock. So all the teeth and all the holes in the side plates are raw aluminum. Is that correct? Kind of defeats the purpose somewhat. Any other options that you like on these sprockets? Super light option(extra holes), etc?

http://sprocketspecialists.com/product/honda-cb-750-k-rear-motorcycle-sprocket-yrs-70-76-sku-209-2/

I'm trying get all my parts together ...ducks in a row, so to speak.

George

Justind97 · « **Reply #5 on:** August 02, 2015, 06:12:16 AM »

I found a place on the west coast last year that makes custom front sprockets.

I managed to get 520s for my CB550. I'll have to go back in my records to figure who it was.

bwaller · « **Reply #6 on:** August 02, 2015, 06:45:03 AM »

Any rears (Titan Tough) from Sprocket Specialists were always delayed a couple days for anodizing, and were done after machining. The JT's I haven't had luck finding lately but in my case the countershaft is CB360 based so the spline dimensions are different from the 550's & 750's. I still recommend holding out for a thicker center width, but maybe Justin will find his source.

I've been using the 520SR chains, not top of the line and I replace after four weekends. The 520RX might be a better option. (I use them on the street) but you don't need a sealed chain for your racebike. ((don't want to start an o-ring chain discussion)) Some of the listed info I could never understand. Identically sized pins, side plates, but longer pins because of sealed rings offer higher tensile strength??

joesmotos · « **Reply #7 on:** August 02, 2015, 08:07:24 AM »

http://www.rebelgears.com/

i called and ordered some rear sprockets from these folks last week,might want to check them out also..

Old Scrambler · « **Reply #8 on:** August 02, 2015, 09:27:49 AM »

You beat me to it, Joe..............REBEL GEAR is fast and will custom cut to your spec.....................AND GAVE ME A FREE SPROCKET WHEN I PROMISED TO CARRY HIS DECALS ON MY BIKE

simon#42 · « **Reply #9 on:** August 02, 2015, 12:31:14 PM »

i use a non o ring chain on 250's but use the mvxc on the larger bikes

a 520 mvxc will do two iom TT practice sessions and a six lap race on a bmw rr1000 making 220 hp , i then stick them on one of the road bikes to finnish them off ...... waste not want not !

joesmotos · « **Reply #10 on:** August 02, 2015, 01:35:41 PM »

hey i told that guy i was going to Bonneville too and he didnt give me a free sprocket...lol

gschuld · « **Reply #11 on:** August 02, 2015, 06:20:14 PM »

God info.

Brent,

That makes sense having the anodizing done post machining, it just didn't appear that wy in one of the photos. Thanks for straightening that out. Do you get the rear aluminum sprockets anodized for wear resistance or aesthetics? Both?

I'd very much like to have the thicker center section with a new 520 front sprocket. I'll try to contact JP Sprockets in the morning to see if they can get me one.

Joesmotos/Old Scrambler, I'll check into Rebel Gear, thanks

Simon#42,

The mvxc chain (up to 1100cc modern motors) is a bit overkill for a big bore cb750, but appears to be the next step up from the 520sr chain (mean't for 350cc modern motors)

George

bwaller · « **Reply #12 on:** August 03, 2015, 04:26:30 AM »

For the small price my thinking was to get some extra wear.

voxonda · « **Reply #13 on:** August 03, 2015, 08:28:37 AM »

I use the 520 R6 rear sprockets because of their nice appearance and availability. But rode for years with other wheel where I attached a blind 520 to.

No pic of the 750 front sprocket but here one of a Suzuki500 I have done before. No need to search for hard to find 520 front sprockets just turn down the 530 ones.

gschuld · « **Reply #14 on:** August 03, 2015, 11:15:00 AM »

I just spoke with Richard over at JP Sprocket in Georgia. He could only cross reference a 15 tooth with the 11mm plus thickness I preferred in a 520 chain with the right output shaft spline and bolt spacing. H recommended against taking a 530 front sprocket an milling it down as the surface hardness is reduced quite a bit once you take off more than 1mm.

He was kind enough to offer to do some research with the other suppliers he knows to see if he can come up with something better, like a 17 tooth.

He definitely recommended using a 11mm or wider center section to help stabilize the front sprocket. The other front 520 sprocket I have seen so far have a much thinner center, which he said is fine for street use on a more stock engine.

So no answers on the front sprocket as of yet. Good chain and read sprocket options it seems.

Not even sure where I would look for a custom made front sprocket if necessary.

George

Tintop · « **Reply #15 on:** August 03, 2015, 03:47:38 PM »

I used Rebel Gear for the 520 rear on my 550, and the custom rears for the sidecar. The 550 front is a stock 530 turned down by a local machine shop.

Kickstart · « **Reply #16 on:** April 19, 2016, 10:40:44 AM »

Opening an older thread - sorry.

George, did you ever end up doing the 520 conversion?
I was also doing a search for front 520 sprockets and came across the cognitomoto one (you have a picture in your first post above). Was there a concern it might not be thick enough (they don't list that spec on the site)?

I'm probably going to run a stock 530 again this year, but was thinking about trying to lighten things up a little more.

Thanks,
Chris

gschuld · « **Reply #17 on:** April 19, 2016, 04:48:58 PM »

Chris,

Sure, I went the 520 route. I followed the recommended path and went with JT sprockets for the 2 fronts and Sprocket Specialties for the rear. And I bought an x ring EK 520 chain. The chain is somewhat overkill and potentially robs a tad more power, but I'm fine with that.

George

Haybus · « **Reply #18 on:** April 19, 2016, 08:30:29 PM »

George, are you road racing this season? I bought my 2 rear sprockets and 1 front from Rebel Gears. Fast and cheap ($75 total). They source the front but machine/anodize the rear aluminum sprockets. I got about 32 dozen Rebel Gears stickers in the package too!!

Alan

gschuld · « **Reply #19 on:** April 20, 2016, 03:08:35 AM »

I've had mine in for a while now. I'm a bit behind schedule from where I'd like to be right now, but yes I plan on racing a bit this year.

George

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Author Topic: 520 or 530 chain/sprockets for a cb750 based road racer? (Read 5261 times)