Topic: Installing new chain/sprockets... Any tips?

[DammitDan]

Like the title said, I'm installing new 17 front/38 rear sprockets on my '82 CB650, and a new 104 link 530 Tsubaki HQR 104 link chain.  I've never had to install new chain/sprockets on a bike before, so is there anything in particular I need to know about, or any tips you're willing to suggest?

I'm hoping the chain is the right length...  Would it make much difference if it was 2 links too long?  The manual was extremely vague on how many links were supposed to be in the chain, and I found different specified lengths from different sources.  The bike is an '82 STD with an '82 SC engine installed in it, so I wasn't sure if I should choose the 104 link for the SC engine or the 102 link for the STD frame.  How hard would it be to cut the chain to the correct length?

Whew, that was a lot of questions!

[Einyodeler]

The standard `82 650 came with came with 17 tooth front and 39 tooth rear sprockets , chain is a size 530 with 104 links.
The `82 SC Nighthawk used the same 17 front sprocket but a 38 rear and the chain is 106 links due to a longer swingarm length , the only 650 that used a 102 link chain was the 1979 model.
The Tsubaki HQR is a heavy-duty standard chain , so you should`nt have any width clearance problems.
As far as cutting chains,on my 500s it calls for a 98 link and I always buy the 100 because they`re easier to find. I just use my benchgrinder to grind off one link and I`m good to go.I always order a couple of extra clip connecting links and carry those in my toolpouch in case I ever need to remove the chain,do not reuse the old clip.
And when installing the clip the closed end points the same direction as the chain travels.

[Kevin D]

1) Measure twice, cut once.

2) If your new sprockets are the same size as the old, then your chain should have the same number of links - give them a side by side inspection. If the sprockets are smaller, you may need less chain.

3) If you need to shorten the chain and you don't have a chain tool, use a hand grinder to take off the ends of the pins down to the side plate, then push them out with a drift. Easy job.

4) I've never tried to use a chain that was too long, but it should work (in a pinch) if there is enough adjustment in the swing arm slots.  2 links = 1 1/4". Extra length split between top and bottom - wheel will be 5/8" further back (I think, but - too much math for Sunday morning). When the new chain stretches it may have to be cut anyway. Sounds like a bad idea to me. The axle should be near the front of the slots for a new chain and towards the back for an old one. My new chain put the axle just short of the first mark.

5) You haven't mentioned the master link and I don't know what an HQR has. I don't have any experience with riveted master links and you may find that you need a chain tool tool anyway.

6) I use a cut up coathanger to fish the chain over the back sprocket and through the chainguard, and make the master link at the rear sprocket. For clip type link, closed end of clip points in direction of rotation.

7) If you don't trust the adjustment marks on the swingarm, check wheel alignment - that's another thread.

Measure twice, cut once. What's important is the number of pins in the old chain. Don't cut unless you are certain.

I've lost count of how many chains I've put on my cycle. I put a new DID standard chain on this year and cut down from 110L to 100L. I tried an o-ring chain - it might have been the last one I ever put on this bike, but it hit the chain guard so I couldn't use it.

[Bodi]

As far as length and sprocket chages goes:
Each tooth plus or minus means the axle will be 1/2 the chain pitch closer or further away from the engine... that's about 1/4 inch at the axle. So a tooth or two change won't be a big deal. Changing the rear sprocket can mean quite a few teeth different though. It really isn't a good plan to try and calculate the length... measure it and you'll be certain. Put on the sprockets you want and lace up the chain with one end over the rear sprocket and blcok the wheel so it won't turn and drop the chain off, the end should lie around the middle of the back of the sprocket. WIth the adjusters set about 1/4 from tight, pull the long end tight and wrap it around the sprocket and see if a pin you can cut the chain at lies next to the free end. You can only cut where the plates are on the inside at the pin you want to cut.... go looser one link if it's wrong. Tie a wire or something through the outside plate hole where you need to cut it. Sit down and take a nother look and make sure you measured correctly.
If you want to change back to stock gearing or do more experiments... think about that too. You can always shorten the chain later but you can't make it longer easily. Cutting it as long as will work (with some room in the adjusters) lets you experiment a bit and cut it shorter if you need to.
Cutting and joining the chain is easiest with a chain breaker tool (pretty cheap) and clip links. Riveted links are stronger, true... but what a 150HP sport bike needs is gravy for an SOHC4; clip links will be plenty strong enough for you.
Lenthening the chain is possible with 1/2 links but the chain will be quite a bit weaker; they don't make them as strong as modern bike chain, just for industrial chain loads.

[DammitDan]

Well, the front sprocket is 1 tooth bigger and the back is 1 tooth smaller than stock.  I do a lot of highway cruising on the bike, so I wanted to lower the high-end RPMs as much as possible while still retaining some low-end torque (but not all... certainly didn't need that much oomf!).  It's good news to hear the 104 link is the correct one for the STD frame...  means I will have plenty to play out with the chain adjuster to compensate for the 1-tooth-smaller rear sprocket

Wish me luck, I'm off to the parking lot to start my work.

[DammitDan]

Well work's done... Took about 4 hours total having never done it before (that time includes shining up the rear rim and chain guard... man they're super pretty now!).

I would never have expected the original chain to be such a pain to get off... I decided to just break the damn thing with a screwdriver and a hammer instead of going through the pains of taking all the swingarm apart and disconnecting the rear shocks.  Boy, what a major job that turned out to be!

However, after installing the larger front sprocket and the smaller back sprocket, it does run at a lower RPM at higher speeds.  Unfortunately I could only get it up to 50 or so before the rain started coming down, but it was running under 4k at 50.  That's good 

I have to thank whatever higher being there is up there for holding the rain off till I could finish putting everything back together again.  Not having a nice and dry garage sucks!