Topic: K8 Chain/Sprocket Replacement Questions

[Rosinante]

I hope the photo appears.  Apparently, this is not  "link" for the purpose of counting chain links.  This must be two "links."  My chain has 44 of these, and stock chains on K8 bikes have 88 "links," I believe.  Correct?

[Rosinante]

Alright.  Questions:

The chain on my bike is not adjusted to the red "replace" section on the sticker located on the adjusting bracket, but I don't know who put that sticker on, or when it was attached.  I do know the chain was replaced without replacing the sticker, and without also installing new sprockets.  The teeth on the small sprocket are visibly worn.  further, when I adjust the chain properly so that the tightest it gets is 3/4", other portions of the chain are WAY looser than 3/4".  With a new chain and sprockets, will I be able to adjust the chain so that it does not have this variability in tightness across different sections of the chain?

Stock K8 bikes have size 630 chains with 88 links.  Front sprocket has 15 teeth.  Rear sprocket has 41 teeth.  I am pretty sure about this, unless someone disagrees.  My chain does have 88 links and the front sprocket has 15 teeth.  I did not count teeth on the rear sprocket.  I just want stock sprockets and chain for this bike.  Yes, I know a 530 chain would be plenty strong. 

Manual says that to remove or install a non-master link chain, the transmission cover has to come off!  Is this really true?  In addition to the rear swing arm?

I think a properly-installed master link and clip are just as reliable and much easier, correct?

But.....I think that master link and clip can be challenging to install properly.  Particularly with a 630 chain.  Any tricks or suggestions you can offer?  I think the challenge is in getting the master link squeezed together firmly enough that the clip full engages.

Any suggestions of a good source of chains and sprockets?

[BenelliSEI]

When restoring our K7/8 bikes a few years ago, my buddy Gary and I stayed with the stock sizes of chain and sprockets. I don’t think the “0” ring, 630 chain we bought was available with a clip link.  I picked up a relatively inexpensive “chain rivet tool”, that did all three. If you can find a modern 630 chain that comes with a clip link, I wouldn’t hesitate to use it.

The only cover you have to remove for chain replacement is the small cover over the output sprocket (two screws). Warning: on K7/8 models in particular, this cover appears impossible to remove from the bike. It does come out, in one certain direction......... Good Luck!

[Rosinante]

Yes, that cover does come off but you have to hold your mouth just right. 

The service manual says the shift lever and transmission cover have to come off to remove a non-master link chain.  Hm.

[denward17]

I cut my old 630 chain off with a vibrating metal cutting tool, I then used a 530 chain with a master link and clip (new 530 sprockets as well).

I didn't want to remove the swing arm just to remove the chain.

[Erny]

I have K7, all stock original.

As of cover - it is the one mentioned by BenelliSEI that you need to remove and yes, looks not possible to remove, but it is. Putting it back again can be even more challenging  Search here on forum some member made video how to take if off/put back on.

Chain - my K7 had original 630 chain (9k miles) but few O-rings were shot, so I had to replace. As sprockets were like new I dediced to go again for 630 chain, I bought endless DID from Amazon 88links. So swingarm had to go off, what I found finally as good opportunity - swingarm collar (shaft) required a lot of cleaning and lubing after 45 years, there was only dried grease inside. At the same time you can clean/check grease nipple too and eventually clean/de-rust/paint swingarm. Job is not difficult.
For these kind of chains, I think only option is endless chain or rivetting link..

If I need to change chain again (I cannot imagine how I can manage to wear out that monster chain), I will install 530 or even 525, much lighter and more HP on rear wheel

[Tracksnblades1]

When restoring our K7/8 bikes a few years ago, my buddy Gary and I stayed with the stock sizes of chain and sprockets. I don’t think the “0” ring, 630 chain we bought was available with a clip link.  I picked up a relatively inexpensive “chain rivet tool”, that did all three. If you can find a modern 630 chain that comes with a clip link, I wouldn’t hesitate to use it.

The only cover you have to remove for chain replacement is the small cover over the output sprocket (two screws). Warning: on K7/8 models in particular, this cover appears impossible to remove from the bike. It does come out, in one certain direction......... Good Luck!

👍 Plus +1..

Buddy’replaced his endless 630 chain on his 79 CBX 1000 with a RK Gold Oring 630 chain with a master link.. Never had a problem with the master link and he ran the H out of it.  It was a *itch kitty to compress the Orings enough and get the lock engaged in the grooves at the same time. Same as a good 530 oring chain with tight clearance too. Just follow the recommended lock direction of travel. So a weed or road debris doesn’t pop it off. The 530 supposably frees up some horsepower and runs a lot quieter (subjective). My buddy changed his 79 CBX 630 over to 530 the second time when the kit for it  or the newer CBX’s came out with the 530 chains @ 105 horsepower.  😁

[PeWe]

#
I didn't want to remove the swing arm just to remove the chain.

I have used riveted chains since 2013.
No reason to open chain. That is an old myth for non CB750 owners.

I had that in my mind when I mounted a strong riveted chain for first time so I ordered 2 extra master links. I found a way to avoid open master link at wheel removal or pulling engine.

I have pulled engine twice on my K6 without open the extra strong riveted chain.
First chain was DC chains strongest with solid rivets.  Need a good riveting tool.

Now strongest DID with hollow rivets. 530ZVMX. Cheaper reveting tool possible.

I ordered extra master links with chains just for sure if chain had to be opened or mistakes during riveting wich happened.

Only thing to do when removing rear wheel for replacement of tire/ wheel or pulling engine:

- Remove chain guard and cover on engine.
- Release and push wheel max forward for chain slack.
- Lift front sprocket off the outgoing axle with chain and push backwards. Work fine on my K6 and K2.
I do not know if later cases from K7-8, F2-3 with a protrusion at outgoing axle will be an obstacle, probably not.

Now can chain be lifted off rear sprocket and wheel can be taken off.
Or engine can be pulled out of frame.

My stock K2 has DID 530VX riveted chain.

I do not trust the clip chains. I remember close moments in the 80's when I found clip to be missing. Side plate still on since it sat hard.

The stronger chains have not clip option.
The stock restorer need old style to get it 100% stock. Maybe not much riding, more for display or ride to special meetings.

Crack the case due to a bad chain/missing clip will cost a lot in money and time.

[rotortiller]

630 rear sprockets last forever on 77/78s. Chain does well too until the o-rings go bad.  I have used both rivet and clip masters on many bikes including CB750s and never had an issue. One thing about the rivet link is that it can be installed too tight and add excessive friction to the o-rings causing noise and vibration while the clip links do not. Both work fine when installed correctly. Like anything a quick inspection of the final drive once in a while is wise, just like looking at tire tread wear. Remember some guys would screw up the lord's prayer, that is provided they actually knew how it went. You can down size the chain and sprockets and get a wee bit more power at the K7/K8 rear wheel however since these bikes are heavy old pigs the gain is not worthwhile in my experience. Like someone stated the engine chain cover is a pain until you figure the install angle and twist but that is quickly forgotten since the system is very reliable.

[PeWe]

Distance plates on both sides where o/x rings are will make riveting easier. Avoid a Z shaped chain when riveted too hard together.

Some chains include those.
I have home made a friend made, look like a fat E, 1.3mm thick.
Make side plate to sit too tight before or during riveting a mistake I have done before I  got distances.
Grind off the rivet and push out master link. That was with solid link.
Time for a new master link.

When I had those problems I remembered how easy the clip links were. But riding the bike without worries about a chain that can open is well worth the hazzle.
The modern good chains will not stretch as before.

I snapped one chain during a heavy acceleration in the 80's due to a too sloppy chain. D.I.D 50HDS o-ring chain.

My cases were lucky then. Only the chain guard that lifted off with swing arm brackets still on, a cut in licence plate and scratched hub and rear sprocket carrier. Everything happened during a second.
Ca 120kmh, geared down to 3rd gear from 5th and WOT. 836 setup making closer to 80whp. 17:48 gearing.
That was on German Autobahn where I had to pass slow going traffic. The other lane traffic held min 160-170kmh.

[Rosinante]

I am still hoping for suggestions regarding WHERE to find a chain/sprocket set for K7-K8 bikes.  88 rollers, 15T and 41T sprockets.  Looking at what's available, the set that is closest to Washington State is in England somewhere.  Expensive, + shipping + VAT.  The next nearest one is in Germany.  Another one is in Japan.

Also, in looking at the pictures and descriptions, it looks like there are differences between these sets.  One front sprocket looks flat and the other has a 'hub,' so I am not confident about fitment.  BTW, both the continuous and the master-link types are available (if these three sets will each fit properly, which is uncertain).

[denward17]

I am still hoping for suggestions regarding WHERE to find a chain/sprocket set for K7-K8 bikes.  88 rollers, 15T and 41T sprockets.  Looking at what's available, the set that is closest to Washington State is in England somewhere.  Expensive, + shipping + VAT.  The next nearest one is in Germany.  Another one is in Japan.

Also, in looking at the pictures and descriptions, it looks like there are differences between these sets.  One front sprocket looks flat and the other has a 'hub,' so I am not confident about fitment.  BTW, both the continuous and the master-link types are available (if these three sets will each fit properly, which is uncertain).

The unavailability of the 630 size was the main reason I went with 530.  When I looked I don't remember even finding any available, or it was much more expensive.  Good Luck.

[PeWe]

Wemoto in Europe seems to have 630.
https://www.wemoto.com/bikes/honda/cb_750_k7/78/picture/chain_did_v_o-ring_super_heavy_duty

The modern power bikes with lots of hp run 525 so modern chains have developed.

A friend has an Aprilia Tuono, around 170hp on crank. 525 chain.

[Rosinante]

I'd prefer to stay stock but am open to the 530 chain idea.  However, my concern about fitment would remain.  I question whether just any ol' 530 chain/sprocket set would work.  Sprockets can be offset.  Perhaps nobody knows how many 530 links are equivalent to 88 630 links.  When I do order a chain/sprocket set, I want to be sure it will fit.

[Rosinante]

Alright.  Will any 530 chain/sprocket set, that fits an earlier CB750K (72-76 for example), also fit my K8.  Are they exactly the same?  Actually, we know they are not since the earlier front sprockets are attached using two bolts and the K7-K8 sprockets are 'floating' and are attached with only the one center bolt. 

Please be patient with me.  I am trying to understand.  I do not want to order a set and then have to return it.

[Rosinante]

Let me ask this:  How many 530 chain links on your CB750K?  Some kits for these bikes have 100 links and at least one has 108 links.  My swing arm is longer than the K0-K6 swing arms, I believe.  I wonder if the 108-link kits allow for this.  I can always remove links.

Or just tell me how many 530 links are needed on a K7-K8 CB750K?

[denward17]

I can tell you what I ordered and it works for my K8.  This based on stock swing arm.

I got an 0-ring chain (530) with 2 different master links that can be either used with a clip (which I am doing) or a link that has to be inserted with the tool.  Chain came from Dennis Kirk.
530 MAX-O Chain - 530MAXO-104
Part #: 110946104

It is 104 links, and if the chain stretches much, I might have to take a link out, but right now with just under 20 miles is ok.  I'm about half way on the adjustment.

The sprockets I purchased are JT sprockets: (Randakks)

Note: the front sprocket is for a CB650, but fits perfect.  Mine came with a shoulder on one side, that gets mounted toward the engine.  I mounted with the shoulder out the first time and the chain would rub the engine cases.


Sprocket - Drive - Front - 530 - JTF 338 - 17 Tooth - CB650

SKU: BAJTF338-17

1
Sprocket - Drive - Rear - 530 - JTR 284 - 48 Tooth - CB750

SKU: BAJTR284-48


The 17/48 teeth ratio works out to be close to stock.  Mine is not geared for interstate travel.  Your mileage may differ..........

[Don R]

 I did a 630 to 530 swap on a 77K but I'm not positive it's correct, the bike has had transmission problems and hasn't gone many miles since.

 I think some ebay sellers may provide industrial chain rather than dedicated motorcycle chain. Stick with a brand name. We used to run farm store chain back in the day and did get away with it, but I love my engine cases too much to chance it now. 100 links is fairly short even on an early K. I buy the 108-110 and shorten to fit.
 The sticker on your swingarm was permanently installed new.

[newday777]

Let me ask this:  How many 530 chain links on your CB750K?  Some kits for these bikes have 100 links and at least one has 108 links.  My swing arm is longer than the K0-K6 swing arms, I believe.  I wonder if the 108-link kits allow for this.  I can always remove links.

Or just tell me how many 530 links are needed on a K7-K8 CB750K?

Just get a 120 link 530 chain and cut off the excess once you figure out how many links you need, adjust the rear wheel to be about 1/2 way in the slot and set the chain on the sprockets to see how many links you need. Cut off the extra with an angle grinder.

I haven't found a link for how many links needed to convert but here's a good one on the sprockets to use.

https://www.cb750.com/threads/78-cb750-f2-chain-conversion.7213/

[Rosinante]

That is enormously helpful, denward17.  I will try to return the favor.  Read further:

The sticker on your swingarm was permanently installed new.

The sticker on my bike was likely installed at the factory.  But.....the service manual K7/K8 supplement says to replace the sticker when a new chain is installed, and describes the procedure.  The width of the green section on the sticker is about 3/8" wide.  In other words, when the chain is worn enough that the adjuster bracket has moved more than 3/8", then it is time to renew the chain.  Which is not very far.  Also, this assumes a 630 chain.  And it makes some sense too.  This chain lives in a harsh environment, does an important job, and can create a safety problem at failure.

[Rosinante]

FWIW, I was able to order the chain (120 rollers, clip style, 530) and the sprockets (JTF338.16 and JTR284.43) from the Dennis Kirk website.  I hope they fit.  I think they will.

[Ellz10]

I snagged two brand new Diamond xdl-0 630 chains, but had to scour the web for months waiting for the master link to pop up for sale. Went thru the process of cleaning and luring them, they work and move free and great.

As mentioned before, absolute nightmare, in my opinion, that you need to remove the gear cover to be able to remove the chain.

But I'll stick with my heavy 630, I like it.

[Rosinante]

Well, with the master link, you don't have to remove the gear cover.  Also, I R&R'd mine prolly 4 or 5 times in the past three days and now it is easy.  And finally, with a non-master link chain I would think removal of the swing arm is the bigger PITA.

[madmtnmotors]

You do not have to remove the transmission cover. I did a video of the front sprocket cover removal because by the time I need to remove it again I end up forgetting how I did it last time and struggle with the thing for 30 to 40 minutes. I finally preserved the process in infamy:

[bryanj]

When the bikes were new the only place to get a chain was Honda and in the package came a new wear sticker so you fitted the new, endless, chain tensioned it correctly and fitted a new sticker with the line s showing maximum life.