Topic: replacing drive chain cb750k

[Wisco78k]

Hi all,

So it looks like I need to replace me chain on my 78' cb750k, according to the shop where i got my tire replaced. The spokes were also loose but ill be doing that on my own. Said there are some kinks but ive never felt anything weird. Is it insanely unsafe to ride it now?

What I want to know is how hard it is for me to replace. I have an average amount of tools and mechanical know how. Im not an excellent bike mechanic but mechanically inclined. I was wondering if this is something I could do in my driveway? Do i Need any special tools?

Also do I need to replace the engine and rear wheel sprockets when I change the chain?
Any opinions on O-ring chains for the honda over the old style.

I know that was a lot but any help would be great! I just dont want to pay some shop 200+ dollars to do something I could do. Thanks for the help all!

[LesterPiglet]

Putting a new chain AND sprockets on is simple enough. It's best to get new cogs with a new chain. I have no experience with the 750 so can't comment on chain type.
I would be more inclined to pay for someone to fix my spokes as I couldn't be bothered trying to true the rim.

[bollingball]

I would not ride it if you don't have to. You should be able to do it. Be prepared you should go ahead and look at the brakes,bearing and cush drive. Read up on the procedure in the shop manual then ask here if you don't understand
Tool a bearing retainer remover homemade maybe a chain tool depends on type of chain.
Ken

[ZanVooden]

Its really not bad to do. Depending on what chain you by, you may need a bench grinder and a hammer and punch to cut the chain to length.
The sprockets should be changed with the chain. Look up JT sprockets website and find the sprocket part #'s you need and then order them through amazon. I recently got a front and rear for the 78F for $40.

If you need help I see you're in Madison, I could probably give you a hand at my shop.

[DJ_AX]

imho ...  insanely unsafe... no ..
unsafe.. maybe..

Easy to change.. Absolutely... (and rules out the above "maybe" (which some consider insane))

You don't have to change the sprockets but it is highly recommended... as you can see... I'd say necessary if they show significant signs of wear (crooked teeth)

I've always just gone with a good ol heavy duty DID chain...
with care it will last.

[lucky]

You can do it your self.
Get #530 spockets and chain. Get rid of the #630 chain and sprockets.

#530 chain is used on 150HP motorcycles.
Just a REGULAR chain with masterlink clip.
You need to put the bike on the center stand on a level spot.

Start by loosening the rear wheel axle nut.
When the axle is loose you can move the rear wheel forward.
CAUTiON
do not kick the rear wheel forward as the bike will fall forward off of the center stand!
Then pull the rear axle out. Make sure to take note where the spacers go.
Then you can lift the chain off of the rear wheel sprocket and remove the rear wheel away from the bike.

Then remove the chain either with the master link or by using chain splitting tool .
Put the engine in gear.
Remove the front sprocket.

Clean the rear wheel while you have it off and install the new rear sprocket.
Install the new front sprocket.

After the rear wheel is back on make sure it is all the way in the forward position.
Do not tighten the axle nut yet.
Put the chain on, (112) links and measure how much is needed. Use your chain splitting tool and remove the unwanted links.

 Install the chain,install the master link and clip.

Tighten the chain adjusters until the middle of the chain will only move up or down 3/4 inch. Tighten the axle nut.

Take the bike off of the centerstand and tighten the front sprocket bolt or bolts.

NOTE: as others have said while the rear wheel is off get the wheel trued.
         Get new cush drive rubbers. The ones you have are 33 years old and the hot braking forces have acted on those rubber parts.
Check the wheel bearing for smoothness and if you can just replace them.
sometimes you can use the wrench from your 4 inch grinder to loosen that bear retainer nut.

You can get new wheel bearings from a bearing supply house.

[DJ_AX]

and if you decide to just change the chain for now ...

While on the center stand ... just take the clip and faceplate off of the master link.. (assuming your old chain has a clip on type) connect the end of the new chain to the old and just pull it through till the old chain is out...
You should probably use a new clip on master link too.

[george]

Of course you can do it ! Easy job! If you still have the stock 630 chain , maybe consider the 530 conversion. I just did it on mine and it , too me is so much smoother. Plus there are many more gearing options available with the 530. I ordered this on ebay, 17/46 with a 530 o-ring chain for like $135.00, JT sprockets, bikemaster chain, not the best but better than I had !
Let us know we'll post up a gearing chart and good sellers !

[Unkleskunky]

Of course you can do it ! Easy job! If you still have the stock 630 chain , maybe consider the 530 conversion. I just did it on mine and it , too me is so much smoother. Plus there are many more gearing options available with the 530. I ordered this on ebay, 17/46 with a 530 o-ring chain for like $135.00, JT sprockets, bikemaster chain, not the best but better than I had !
Let us know we'll post up a gearing chart and good sellers !

Hey I would love to see that chart and vendor info.

Thanks in advance.

[Black 750K8]

+1 for the chart. Did the 17-46 put your RPMs back to stock and how many links??

[lucky]

Remember that on that K8 that the 4th and 5th gear were higher than previous CB750's.

[70CB750]

Google:

CB750SOHC-Gearing-Chart1.xls

or this link:

http://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=1&cad=rja&ved=0CC0QFjAA&url=http%3A%2F%2Fmanuals.sohc4.net%2FCB750K%2FCB750SOHC-Gearing-Chart1.xls&ei=2NUMUq2pK-SQyAGnoYHwDw&usg=AFQjCNHzB_59z3g4m8ufElPOleLB3m5gnQ&sig2=j2rcSOM2Dnwlb0ZJw7ucHw&bvm=bv.50723672,d.dmg

[lucky]

Hi all,

So it looks like I need to replace me chain on my 78' cb750k, according to the shop where i got my tire replaced. The spokes were also loose but ill be doing that on my own. Said there are some kinks but ive never felt anything weird. Is it insanely unsafe to ride it now?

What I want to know is how hard it is for me to replace. I have an average amount of tools and mechanical know how. Im not an excellent bike mechanic but mechanically inclined. I was wondering if this is something I could do in my driveway? Do i Need any special tools?

Also do I need to replace the engine and rear wheel sprockets when I change the chain?
Any opinions on O-ring chains for the honda over the old style.

I know that was a lot but any help would be great! I just dont want to pay some shop 200+ dollars to do something I could do. Thanks for the help all!

You do not need a O ring chain.
Just a high quality chain.

[70CB750]

I knew you will say that, lucky 

[acollin]

You've gotten some great advice on drive chain replacement, but given what you say about your own mechanical understanding, you should be as fearful or more fearful about all those loose spokes you say that you will take of yourself.

Truing spoked wheels is not a simple task and is loaded with potential dangers. Make certain you read up on and seek advice on spoked wheel truing.

Good luck-- but once you've corrected the chain/ sprocket issue, I'd be looking into that wheel issue before I did any serious riding.

[george]

Welcome to the site btw, now one year later I had to look up some info for you , lot's of good sugestions from people here !
This is the seller I have purchased several sets from, nice guy , no issues, send him a note and he will build a combo for you !

http://www.ebay.com/itm/530-Conversion-Chain-Sprocket-Honda-CB750F-77-78-17-46T-/330449530095?hash=item4cf053acef&nma=true&si=06WOmVUb%252Fcf8HSCjT2uQMIGNjb8%253D&orig_cvip=true&rt=nc&_trksid=p2047675.l2557#ht_1928wt_679

http://www.dropbears.com/u/utilities/sprocket.htm

69-76 K series 530 chain, 75-78 F and 77-78 K series 630 chain Still not sure what size chain you have?  Look on the side of the link; it should be stamped there.  And last but not least, if all else fails measure, 530 chains 5/8" spacing, 630 chains 3/4" spacing. 530 chains are cheaper and easier to find and custom sprockets are easier to find for them.
.
Sprocket Ratio Chart?
Dropbear's site has a complete table showing the ratios for different sprocket combinations. A quick and dirty but effective method is to divide the number of rear sprocket teeth by the number of front sprocket teeth. E.G. an 18/48 530 stock ratio would be 2.66:1.



Hey I would love to see that chart and vendor info.

Thanks in advance.
[/quote]
Hope this helps, it really had a very positive affect on my K8 when I switched from the 630 to the 530. George

EDIT : I just noticed he does not have the exact set (package deal) any longer, just search his site :

http://stores.ebay.com/Jawzys-PowerSports/_i.html?_nkw=cb750+1976&submit=Search&_sid=200314105

for cb750 1976, or call him he may be able to save you some money, as I said , very good seller. George

[Black 750K8]

Hi all,

So it looks like I need to replace me chain on my 78' cb750k, according to the shop where i got my tire replaced. The spokes were also loose but ill be doing that on my own. Said there are some kinks but ive never felt anything weird. Is it insanely unsafe to ride it now?

What I want to know is how hard it is for me to replace. I have an average amount of tools and mechanical know how. Im not an excellent bike mechanic but mechanically inclined. I was wondering if this is something I could do in my driveway? Do i Need any special tools?

Also do I need to replace the engine and rear wheel sprockets when I change the chain?
Any opinions on O-ring chains for the honda over the old style.

I know that was a lot but any help would be great! I just dont want to pay some shop 200+ dollars to do something I could do. Thanks for the help all!

You do not need a O ring chain.
Just a high quality chain.

You do not need a motorcycle

[tlbranth]

Hi all,

So it looks like I need to replace me chain on my 78' cb750k, according to the shop where i got my tire replaced. The spokes were also loose but ill be doing that on my own. Said there are some kinks but ive never felt anything weird. Is it insanely unsafe to ride it now?

What I want to know is how hard it is for me to replace. I have an average amount of tools and mechanical know how. Im not an excellent bike mechanic but mechanically inclined. I was wondering if this is something I could do in my driveway? Do i Need any special tools?

Also do I need to replace the engine and rear wheel sprockets when I change the chain?
Any opinions on O-ring chains for the honda over the old style.

I know that was a lot but any help would be great! I just dont want to pay some shop 200+ dollars to do something I could do. Thanks for the help all!

You do not need a O ring chain.
Just a high quality chain.

Especially if you're keen on chain adjustments every 100 miles and a wheel covered in oil.

Lucky, for crying out loud, would you just TRY an x-ring chain and get unstuck from the sixties!