Topic: o-ring chain to crankcase clearance on 750 k series

[jsaab2748]

My new RK X-ring chain is impressive looking after installation. But the chain's inner sideplates are WAY too close to the engine case  (at the point where the chain exits the crankcase, at the bottom, and after going around the front sprocket.) I am absolutely certain that it will make some degree of  very light contact during normal operation.
My question is, has anyone ever had to "clearance" the edge of the crankcase in order for the chain not to rub?  This looks possible to do without hurting anything (or striking oil) at the interference point of chain/case. Just wondering if anyone's ever tried this, or had any other issues fitting #530 O ring chain to a 750 k0-k6? Thanks.

[Bob Wessner]

Oh, oh, wish I had seen this thread before buying an O-ring chain for my K0. Shortened it to the required 98 links and am awaiting a riveting tool to join the ends. I saw so many recommendations for O-rings that I never thought this might be an issue. Guess I better do some closer checking tomorrow. 

[Bob Wessner]

Well, I did go out to the garage today to follow up on this issue. I haven’t riveted the chain as yet, but I laid it over the sprocket and put the retrofitted (’69 750) case guard in place and though it’s snug, I could not see where it would contact anything. I wiggled the sprocket on the splines and it still made no contact. Before I commit to this I would like to hear of anyone who has had problems, or not had problems for that matter. Ignoring the cost of the O-ring chain, I would still scrap it for a standard chain if I thought there was even a remote chance of holing a case. Feedback would be greatly appreciated. Thanks.

[MRieck]

It can be very close. I did grind a very slight bit ( maybe 1/16" at the most) of extra clearance at the bottom about 6 o'clock and 7 o'clock. Some chains are wider than others. I'm going to run a DID VM chain (x-ring design).

[andy750]

Ive used only Tsubaki Sigma and Omega o-ring chains (530, 102 links) on both my CB750K4s and have not seen any problem in clearance with this brand of O-ring. Road tested over 1000`s of miles under all conditions with stock sprocket set up. Good luck, Andy

[Bob Wessner]

Thanks all for the feedback.

[Hop on a Honda]

Oh Boy what an expensive mess this chain could make Even break hearts and cases.
I did the same but the chain cover told me of the rediculous tight clearance.

I have seen a Regina (Italy)  530 on a CB 750 which seemed to have had some success.

Dave Australia.

[Bob Wessner]

Well, I took a second look at the clearances. Then measured the difference in the chains. Naturally, the O-ring is noticably wider. Sooo, I decided to at least for the time being install a standard chain, no O-rings. I think I'm risking enough doing the work on this bike myself anyway. As it is, I'm thinking of hiring a high school kid to follow me around in his pick-up truck on my first ride just to retrieve any pieces that might fall off.   

[jsaab2748]

Thanks for the replies from all you guys, Mikes earlier post described my clearance situation exactly. (tight clearance at the 5 and 7 oclock sprocket positions.) Since I already bought the rk brand x ring chain, I'm considering going the same route Bob mentioned, stock for now and making modifications later on, maybe next winter. Glad I asked though, and again thanks.   jim

[CHUNG]

That Mike wrecked.. Sup Dude, email me?
I have never had any "major" clearence probs with the #530 RK XO chains upto and including an 18 tooth drive sprocket. Quite a few different years and engines included. That Mikey, Gotta head North and meet him some day.... Might learn a trick or two?
A #520 O-ring setup is out there for these bikes?

[MRieck]

That Mike wrecked.. Sup Dude, email me?
I have never had any "major" clearence probs with the #530 RK XO chains upto and including an 18 tooth drive sprocket. Quite a few different years and engines included. That Mikey, Gotta head North and meet him some day.... Might learn a trick or two?
A #520 O-ring setup is out there for these bikes?

What's up Mr Chung. Sprocket Specialist will make sprockets for #520 so it is possible. And yes..it would be good to swap some stories bro!!

[dpen]

what model K? I fitted an "X" ring to my K7 & have had no dramas

[Bob Wessner]

Mine is a K0. I've already eliminated any issues, for the time being installed a standard chain. If the bike doesn't fall apart when I finally take it out on the road, maybe I will install the O-ring later and see how it goes. The side clearances to the case are much closer because the O-ring is wider, but there is still room, even with the very slight sprocket wiggle associated with the splined mounting.

[Kevin D]

Test ride today: new RK o-ring chain (530XSO, 100L, Clip type master link) is striking inside of chainguard lightly at rear sprocket but looks OK at front sprocket. About 1/8" from end of pins to inside case surface. About 1/4" from sideplates to case at sprocket radius. I have stock 18-48 gearing. If the chainguard was 1/8" higher and wider or if rear sprocket was smaller I think it would be OK but since I don't have a chainguard stretcher I will probably be looking for a different chain.

[eldar]

everyone is talking about the 530 chains, what about clearance problems with O-ring 630 chains that are standard on the K8 models? I have the stock setup.

[mrbreeze]

Okay... I've been reading all of the posts and bouncing back and forth to my Dennis Kirk catalog and here are my observations.First of all,my catalog is a 2003 model so I wouldn't be a bit surprised if the prices have jumped up a notch or two (do you think that could happen?) OK.. so I am getting ready to buy new rear tire,sprockets,chain,and (I HOPE!) quiet rear brake shoes.I have decided on Metzeler ME-77 rear tire (4.00x18)and I need recommendation on the rest.I imagine the stock Honda brake shoes are going to be a bit more pricey but does any one know if there is a better way to go? I really don't care if they are pricey as long as I get rid of that DAMN NOISE that they make.Now on the sprockets ....I am seeing 1.Parts Unlimited 2.JT 3.Sunstar....According to price,I am thinking good,better,best so I am thinking the middle one..JT Sprockets. KGHOST says he runs a 18-40 setup that puts him at 4200RPM at 70MPH compared to 5200 with stock 18-48 gearing.Now that is what I want...taller gears but my boss said I might not like it that tall around town.Does anyone run 18-43's? That would seem to be a compromise.As far as chains...ANDY 750 says he runs the Tsubaki or Omega O ring chain with no case clearance issues. Now I don't like the sound of grinding my case for added clearance (UGGH!) or having an oversized chain do it for me (DOUBLE UGGH!) but I would like to run an O ring chain with the 18-43 setup. I don't know if I will need 102 (or even 100) link chain though with smaller rear sprocket plus lowered rear shocks. Any comments on any of this? Thanks.....MRBREEZE

[kghost]

Ok, I can stay quiet no longer.

Chain size is broken down by width and by pitch. For instance, 520 and 530 chains. A 530 chain will be wider than a 520. Both will have the same pitch (thats distance between pins) 5/8 of an inch.

However, the width of each particular chain is also influenced by several factors. Side plate thickness and o-ring size specifically. This is why some people have a clearance issue and some do not. Some people ordered thicker stronger chains.

Now of course everyone wants a big bad latest and greatest no stretch never have to lube it chain.

The problem is: DID for example makes Six 530 chains (or at least thats how many I counted).
Regina about the same.

They are not all the same dimensions. Differences exist in the 530 (and all sizes)

Obviously, a chain off of a 'busa needs to be stronger than a CB750. This means thicker pins and side plates. This means less clearance.

So what does it boil down to? If you want an o-ring or x-ring or whatever, don't order the strongest chain you can find. Do some smart shopping. Check the thickness of the current chain and the one you intend to purchase.

Not all 530 chains are the same.

[Hop on a Honda]

I'll agree with the Ghost who walks!

Chains can be deceptive in width also the CB750/4 Honda would not make enough horse power to pull the spoon out of a rice pudding, that is, compared to some other Bike  brands with large HPs and large CCs and chain driven..
I have placed a heavy Duty Rubber "O" Ring behind the drive sprocket which has settled the new sprocket and also added a couple of MM more gap between the casing and the chain.

When I managed to replace the "O" ring chain back to a DID 530 normal chain I also left the "O" ring behind the Front Sproket. I also feel much more secure with the old chain.
I have seen what can happen to a Crank Case when a chain lets go. What a mess.

Dave

[kghost]

Just a couple more thinks to add to the rant above.

Most chain manufacturers recommend cleaning and lubing every 300 miles. Recommended cleaning agent is usually Kerosene. It won't attack the rubber o-rings. Just clean enough to get the dirt off. If you over soak an O-ring chain you remove the lubrication on the pins behind the o-ring.

Clip type connecting links are 35% weaker than the same endless chain. The clip head goes in the direction of rotation.(the open end should not be in the direction of rotation)

Rivet type conn. links are 95% as strong as endless link chain.

Broken crankcases don't need to happen.
If you run out of ajustment its probably chain time.
If you can pull on the chain at the back of the rear sprocket and see daylight its probably done for.
Chain slack on the rear sprocket should not exeed 1/2 tooth height.
For the really anal amongst us, Chains are normally considered toast after 1.5% elongation (which is usually caused by wear on the pin bushings) 530 Chains measure 5/8 of an inch per link. 19 links = 11.875 inches (no more than .178 stretch or 1.5%) 12.053 = too much stretch

If you replace a worn chain, replace the sprockets

P.S when I went to 18/40 sprockets I had to remove one (1) link from my chain as opposed to the 18/48 to get proper tensioner travel.
 

[dpen]

everyone is talking about the 530 chains, what about clearance problems with O-ring 630 chains that are standard on the K8 models? I have the stock setup.

Rk "X" ring chain fitted my K7 perfectly-should be same for a K8. (the sliding drive sprocket seems to alleviate clearamce problems)

[mrbreeze]

OK...Iwas just out looking at the chain in person....Made some observations....First of all,the chain is shot to hell!!!!...Just as I thought but had to do my homework between owner manual,shopmanual,and the good people at SOHC4.Heres what I found out....Owner manual says....Measure distance between 20 pins when chain is taunt.New chain should be 11.875(eleven and seven eighths.)service limit to 12.125(12 and one eighth)....MINE WAS 12 And ONE QUARTER!!....Whooooooooops!!!! I have probably been running that chain waaay too many miles! anyhow...I measured pitch and width to determine that it is a 530 chain with 100 links.Nobody has mentioned how many of the notches on the rear wheel adjustment there should be at but mine is a shade past the middle mark.Now to my tech question...The countershaft area chain clearance issue that everybody mentions.I don't know what particular chain is on my bike but from my homework,I find that I have a 530 chain...five eighths pitch...three eighths width but that three eighths width is measured from the INSIDE of the side plates of the link.The outside of the link measures three quarter inch so I gather what you guys are saying is that an o-ring chain outer link diminsion would be more than that and cause a clearance problem.So am I correct to assume that when I shop for an o-ring chain that I should make sure that it doesn't go over three quarter inch wide? Thanks for the help....Later....MRBREEZE

[andy750]

Hi all,
Great topic on the o-ring chains and I agree with all thats been said. MrBreeze, just so you know if you are running stock sprockets on the CB750 (18F, 48 rear) I wouldnt get the 100-link as its a bit tight - just fits and no more. Id go for the 102 link chain and have that extra clearance. Ive run Tsubaki Sigma and Omega 530, 102 link chains on my CB750K4s (x2). The trip bike has gone 16,000 miles on the Sigma chain (this was one 2 month long trip) and required little maintenance and cleaning...lubed every so often but certainly NOT every 300 miles (although of course this would the ideal)...I was more like 500-600 miles but it varied. I should mention though that the chain did break after 16,000 miles on the highway just at the Alabam-Georgia state line as i was riding back to Boston from Mexico (Bud Jordon - SOHC member saved the day by driving 90miles to give me his chain to get back to Boston!!) - the chain did not snap in 2 but came off the back sprocket....fortunately I was able to ride very slowly up the breakdown lane to the Welcome Centre with the chain hanging on by one link.....the Tsubakis are VERY good chains in my experience and I will continue to use them.
hope this helps,
Cheers
Andy in Boston

[kghost]

Hi, Mrbreeze

I would think you could get away with one a little thicker. You might try measuring the sprocket clearance.

Ha Ha sprocket! Anyone else remember "Pet my monkey!"?