HELP reqd:Differences in 5th gear cogs between models????

[Andy Bax]

I have a damaged 5th gear cog (one of the three dogs snapped off) and need to replace it with a std 22 teeth gear-cog (not the available overdrive cogs). I obtained a gear-cog which I was told was off a 1975 XS, however it is slightly different to my gear. My damaged gear cog has chamferred central splines with a circular groove around outside of splines (looks like the gear shaft shim fits against this). The cog I was sent has no chamfers on splines; it also has no makings on teeth to indicate a post 78 cog, nor a circular groove.

If posted some pictures of each cog could anyone offer to identify which model of XS they are off and whether I could use them on my XS-B. I know different part nos are compatible with different models BUT my cog has no part number on it.

I have had the XS for 35 yrs and I am giving it its first ever restoration...I can't let a simple gear problem stop me now.
Any advice would be well appreciated.

 

[gggGary]

You bet, post up some pics, we'll see if we can help.

 

[XSLeo]

I don't recall just which way is which but the divider line was 78. The early was one way later the other. One set up the gear rode one the bottom of the groove the splines of the gear engages with the shaft. The other rode on the top of the teeth of the splines. The shafts and gears won't interchange.
When you say XS-B do you mean an XS1B or an XS650 B?
If you look on a parts seller like boats.net and look up your bike, find the part you need. Now look at this parts number and look at other years to compare part numbers.
This will tell you which years will swap with yours.
Leo

 

[XSLeo]

Almost forgot, Welcome to our little slice of the XS650 life.
Leo

 

[TwoManyXS1Bs]

Here's the bulletin:

 

[Andy Bax]

Great replies so far guys. I have included four sets of photos:
(1) Photo of my bike;
(2) CASE1 5th gear cog (off my bike);
(3) CASE2 5th gear cog off a spare engine I have (don't know what year) and
(4) CASE3; 5th gear cog I bought described as 'from mid-70's XS650'.

Case 1, 2, &3 cogs are all slightly different !!

I need to know:
(1) Confirm my bike is a 1975 XS650B (from engine no 447-302198)
(2) Confirm CASE1 cog is correct one for my bike (it did come out of it!)
(3) Confirm which XS model CASE2 cog is off (from engine no 447-501975)
(4) Confirm which XS model CASE3 cog is off AND, although it is slightly different, will it be OK on my bike.

If anyone can answer these, I'll put you on my XMAS card list!

 

[650Skull]

For starters you have the Euro 76C, IE1 447-300101 - 447-400000 model XS650.

Euro 75B, 533 447-500101 - 447-600000

Gauges and the caliper mounted behind the front 34mm forks give it away as an XS650C

WARNING Downloaded your pics to examine and picked up a virus. Keep me off you Christmas list.

 

[TwoManyXS1Bs]

WARNING Downloaded your pics to examine and picked up a virus.

Sure 'nuff, my android galaxy tab locked-up on pic #10!

Your gear dilemma is beyond me, parts manuals don't show that level of detail, and there are at least 3 major variants of the transmissions, with sub-variants (including European). You could try to download all the 15-years worth of parts manuals, and make a list of part numbers applicable to your version. Of course, that assumes that your transmission is original and not cobbled together from a previous life.

Your methodical list is excellent, making note of recesses, tooth notches and spline types is important. Do the same for the shafts and spacer washers that you have, noting inner/outer diameters and thicknesses, and if signs of gear slides are on the top or bottom of the splines. Trust nothing, some gears may even have come from different bikes.

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