An Adventure in Firsts: '83 XS650 Heritage Special Build/Rebuild

Chains have two styles of links on them, inners and outers. Both are counted when determining total link length but you can't remove just one at a time, you must remove two. So, you couldn't make a 105 link length, you'd have to go 106. The master link is an outer link style. Both ends of the chain must end with an inner link so the master link (outer style) can join them together. When shortening a chain, you start with an inner. To get to the next inner, you have to remove that 1st inner plus an outer, or two links.

When shortening a chain, grind the riveted heads off the pins on the outer plate you plan on removing, then just pry the plate off and/or tap the ground off pins through it .....

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Even if you have a chain breaker tool, it's still best to grind the riveted ends off the pins you plan on removing. It puts far less strain on the chain breaking tool. To determine the length needed, you could count the links but I never do that. I just string the chain on and pull it as tight as it will go. There's no chance of miscounting and getting the length wrong that way.

Since you must remove 2 links at a time, the couple tooth changes we usually make aren't enough to make shortening possible. A 32, 33, and 34T sprocket will all use the same 104 link length.
 
If I may summarise the above discussion - best stick with standard chain length. 104 links. Going for a longer chain and larger sprocket is really only for stunt bikes. Chain breaker/riveter is best for splitting a chain. You can split a chain by grinding the heads of the pins down as 5T has illustrated but obviously don't do it on the bike.

I swapped from 34 to 33 tooth rear sprocket and I think that gives better gearing - there is no noticeable loss of get-up-and-go away from the lights but the engine feels much happier in all gears with slightly lower revs.

Keep going - the fun stuff is still to come.
 
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If I may summarise the above discussion - best stick with standard chain length. 104 links. Going for a longer chain and larger sprocket is really only for stunt bikes. Chain breaker/riveter is best for splitting a chain. You can split a chain by grinding the heads of the pins down as 5T has illustrated but obviously don't do it on the bike.

I swapped from 34 to 33 tooth rear sprocket and I think that gives better gearing - there is no noticeable loss of get-up-and-go away from the lights but the engine feels much happier in all gears with slightly power revs.

Keep going - the fun stuff is still to come.


Yes to that
Some views in general terms.
If the aim is a daily commuter which is a bit uncertain in itself for a 40 year old Motorcycle.
With restrictions in cost and time
Generally speaking the older vehicle the more difficult to keep running with predictability. ( look around at the parking lot after 40 year old cars )
Here on the Forum are people with 40 years of Experience and in most cases a professional background involving Tools and Muscles.
Massive not to say First class Knowledge of the machine.
Those people are well placed to make changes and perhaps can make it work and do the job.
I general terms ( here ) some of these don't have the Motorcycle for riding it more as a Hobby project to do work on .Rebuild and so on
Some don't reach 1000 miles a year here.. and thats fine by me there are lots of people needed to make a world.
Some build a Cafe Racers on a crap bike putting on shiny stuff for $ 4000 ...and then try to sell it on which is virtually impossible

So
With the aims you have ( Daily Commuter ) my view is that you go for stock as much as possible .A bike 40 years old can have challenges in itself
The stock solution is a design well tested in over 10 years by factory designers. It does work in some way.
The only exception is the Ignition system that can be replaced. If problems

Lately there has been talk about Chain and Sprocket And of course there exists also a " Best practice " that factory specs takes care of..
In general terms the chain and sprockets must be matched so that the chain moves relative the sprocket
Not the same point of the chain hitting the same cog on the sprocket .I do believe the rule is even links on the chain and uneven on the sprocket
But again step outside the Factory spec ,, and problems can arise that perhaps is not wanted right now. Adding to the list " TO DO "

Performance wise the XS 650 is not that bad. If you rev it .It is not at sportsbike but a well tuned bike can be enough for most riders .
Handling and brakes not perfect ...but it can put a smile on your face. Fine Driving experience. .. Hitting the line in the curve.
Top speed is enough. Pretty much all the reasons why a parallel twin always has existed. And most likely always will -- it is a sound well working concept.
I have a sports bike with 3 times the power it is not the same thing. Tuning for performance .is in my view not the right way on a 40 years old 650 cc machine.
Again that is only my View. But modifications gives problems sometimes
Last time i bought a set of chain and sprockets --- to joke about it the biggest problem was opening the card board box.
No shortening of chain and so I have done it and can do it. But chains are a mess .Hardened and dirty.
Keep it simple and stock as far as possible is my view -- in this beginning with fewer problems .. se what happens
 
5-16 safety mileage on the rear, 3.5-19 speedmaster up front. He's got a booty. Isn't the 5 the width though, not height
I use this Dennis Kirk tire site for "reference"
You can see by that chart even that a 5.0-16 is more than an inch bigger than a Dunlop D404 130/90-16 for example.(26.4" vs 25.1") And the Dunlop runs larger than some other manufacturers. I have considered much of what you have been contemplating now on your own XS.
That 5.0 rear tire with a stock 34 sprocket will even increase the gearing slightly. Try stock first? I'll just bet in time you look for a 33 however as you did peviously mention 90mph..
Anyway, Cheering you on! -R
 

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Pitch and width. Chain links are measured in eighths of an inch. So the 5 stands for 5 eighths (5/8") pitch and the 3 is for 3 eighths (3/8") width. not really sure what the 0 is for. :umm:
When you buy the sprockets, it should list whether they're for a 530 chain or not. And as long as it's listed for an XS650 the bolt pattern and hole size should be correct.

Hi Jim
Why 3 digits?
How else could BSA put 5/16" width sprockets on my B33 unless there was 525 chain?
 
Quick clarification: in the service manual, when it talks about the drive chain tension adjustment, it says to loosen the rear brake adjuster. Is the adjuster it’s talking about the rear brake free play one (end of rod connected to wear indicator arm) or this one pictured below which I think is for a rear brake pedal height?
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I had assumed it was the FreePlay and I haven’t touched the pedal height one yet or when I took that other chain off..
110 chain arrived fastest so got it and about to measure tension and break however many I need to keep tension correct and rear wheel as far as possible. Or if that doesn’t work for some reason I’ll break it down to 104 and put it on as far back as I can w/ right tension still
 
That's the brake light switch. It's 40yr old plastic and will break pretty easy. Don't touch it unless you need to adjust for the light.
Here's the brake adjuster....

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110 chain arrived fastest so got it and about to measure tension and break however many I need to keep tension correct and rear wheel as far as possible. Or if that doesn’t work for some reason I’ll break it down to 104 and put it on as far back as I can w/ right tension still

I think you will need to count accurately, cut your chain to 104 links and adjust chain tension in the usual way. You can use the old chain to find the correct length, just lay 'em down side-by-side. In other words, I recommend you forget about trying to mount the wheel as far back as possible at least for now. Later you might explore going to an engineer and having the s/arm lengthened if that is what you want.

Remember that when you adjust the chain, the brake torque arm bolt needs to be loosened as well. The brake torque arm is the straight metal rod mounted above the s/arm on the right to the top of the brake. Don't forget to tighten everything up after you're finished.

Finally, remember it's much better to have the chain too loose than too tight. They should call it adjusting the chain slack instead of chain tension.
 
Just for a reference. This Special II is geared 17-32 and the chain count is confirmed at 104 links just now. I like the axle position in the adjustment range here.
I understand the desire to locate the 5.0-16 rear tire rearward instead in in the forward half of the adjustment range.
-R
 

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Setting the brake pedal height correctly is important, and often overlooked. I see many, many bikes with it set wrong. If the bike in Jim's pic a couple posts up is yours, it's set wrong, a bit too high. You want the pedal height even with or slightly below the top of the footpeg rubber .....

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This allows you to quickly and easily slide your foot onto it without having to lift it first. You will need to loosen the adjuster nut on the brake rod before doing this because lowering the pedal height will apply the rear brake.
 
the brake torque arm bolt needs to be loosened as well. The brake torque arm is the straight metal rod mounted above the s/arm on the right to the top of the brake.
Oh, I don't remember seeing that in the manual. Just looked for pics of that part and nothing coming up clear yet as to which part but I'll keep looking and I'm about to go out and finish up (got sidelined by holidays). This is something other than the brake freeplay adjuster I know I need to reset (pictured in #149)?

As for keeping it far back/setting chain at other than 104. The one I bought was 110 so I just broke it down (2 links at a time as you need to). As far as making sure I know the link #, I've just been counting backwards from 110 as I don't have old chain anymore to measure side by side. Broke 2 sets of 2 so at 106 now. 110 and 108 were too long for right tension/slack. I think I can have right tension with 106 and while the last axle setting clearly made it too tight, I think I can get it 3rd to last, which means it'd be on first settings prob @ 104... I don't see why not do this if tension is correct and it's within one of the axle settings on the bike, which leads me to believe it's in a "safe" position/in line with the bike's engineered proportions... Didn't find clear argument online as to what longer chain pro/cons are, and trying not to do/buy things twice. Just two more links, but I'm sure you guys know something more about what that means than I do and have been able to find... (As for swingarm extension, yeah I wanted to do that but from what I read, the # of inches to make it worth it to me would bring down my turning capability/radius pretty significantly). If the amount it knocks it back is negligible, I'll just go to 104 I suppose. Just trying to modify as I go (which I know is frustrating cuz of my learning curve and maybe not recommended to a degree--ie. first do stock then modify--yet again, time and doing/buying things twice are factors here). We'll see what happens when I get out there...
 
Just remember that the more links you leave/further back on the swingarm you set it, the less adjustment you'll have as the chain and sprockets wear. I like to start at the front of the axle slot... gives me plenty of wear adjustment. You can always remove another link when you wear that far, I just like to do it all at once.
 
Oh, I don't remember seeing that in the manual. Just looked for pics of that part and nothing coming up clear yet as to which part but I'll keep looking and I'm about to go out and finish up (got sidelined by holidays). This is something other than the brake freeplay adjuster I know I need to reset (pictured in #149)?
.
The torque arm is designed to pivot, no loosening needed.
 
When you move the rear wheel the brake adjustment they talk about is the one on the rod that coems back from the pedal. It goes through a spring and the end of the lever on the brake plate. The nut on the rod is what you loosen.
Once the wheel adjustment for chain tension and being straight in the swing arm is done, then you adjust the nut on the rod for proper free play.
When I have to cut a chain I have the wheel installed and slid full forward. Wrap chain around front with the ends at the rear Pull snug as I can. Hold on rear sprocket. so the long end laps over the other end. You then can easily see just where you cut.
Remove the chain. I grind off the pins flush with side plate and drive out with a pin punch. Put chain back on. Install Master link. Adjust wheel.
This gives you a chain with the max amount of adjustment room.
Trying to leave the chain longer just means you will have to cut the chain again soon as the chain ad sprockets wear together. This wear occurs in the first few hundred miles of the chain life.
If the look isn't right then get the swing arm lengthened.
Leo
 
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