Nonsense Found Building Bikes

marshg246

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Some of the things I find when building bikes really amaze me! I'm parting out a mess of a bike and using a lot of the parts for a combat I'm building for a customer. The donor bike included the fork internals in the picture. Notice that the bottom of the dampers are aligned and that the rods are pulled all the way to the top. The damper tubes are obviously the same length but either the rods are different lengths or the short one is getting caught inside the damper tube.

Then notice that the springs are clearly different lengths. The long spring was on the short damper rod, so the short spring is not collapsed over time. Fortunately, I have plenty of springs, rods, and dampers to compare against so I can see what is right and wrong.

I wouldn't be quite as surprised but clearly the parts are all new. Also, I don't know where the damper tubes came from because they are not the normal darker colored steel and the bleed holes at the bottom are slightly different sizes (can't see that in the picture)!

This is just an example of the many stupid things I've found in the donor bike - a bike that was supposedly "ready to ride".

Nonsense Found Building Bikes
 
If aloy then possibly RGM's.
Checked today. They are alloy.

I have no idea if poorly manufactured or screwed with by the builder but the holes at the bottom of the damper tubes are .216" in one and .245" in the other and in the originals I have, they are .242" so that's not good.

Even worse is that the rods are the same length after all but in one, the bottom nut was lying in the bottom of the tube and the piston was not on the pin so inside of the tube is now scored so they are junk.

The springs measure 19" and19.5" and are somewhat progressive so they are not a good pair.
 
I agree that having different length springs is not ideal, but I don't think that amount will amount to much in real world riding. You could argue putting it on the brake caliper side would even things up by controlling its inertia more proportionately than having equal springs. Regarding the hole size differences, I've heard of running totally different damper settings in the two legs to arrive at a certain damping behaviour, but I'd be inclined to drill the smaller one. At least the bad one is too small so it's easily fixed.
 
Well, if we’re talking horror botch jobs…

A friend of mine (now deceased) rebuilt a Commando some years ago. He confessed to me that the swinging arm spindle was so tight in the bushes he fitted that it pivoted in the cradle rather than the bushes.

Good job you spotted it says I, now you can rectify… but… he left it like that !!!

Fortunately, he didn’t do very many miles on it.

If anyone has since bought this and discovered a very worn spindle bore in the cradle, I apologise on behalf of my late mate…
 
Well, if we’re talking horror botch jobs…

A friend of mine (now deceased) rebuilt a Commando some years ago. He confessed to me that the swinging arm spindle was so tight in the bushes he fitted that it pivoted in the cradle rather than the bushes.

Good job you spotted it says I, now you can rectify… but… he left it like that !!!

Fortunately, he didn’t do very many miles on it.

If anyone has since bought this and discovered a very worn spindle bore in the cradle, I apologise on behalf of my late mate…
On the MK3 I'm rebuilding, someone in the past somehow got the swingarm spindle in the bushings along with grease. Trouble is that they sanded down the OD of the bushes. So, the bushes rotated in the swingarm, not the bushes around the spindle! That swingarm is in the recycle bin now along with the bushes and spindle.
 
They might have come from Giacomo Agostini's MV. I read somewhere that he had different damping in the two fork legs (secret stuff). His speed had to come from somewhere.
 
In this case, the nonsense is me!

Over the years I've bought out people retiring, dying, in money trouble, no longer interested in bikes, etc.

Once in a while I'm forced to straighten up, clean up, put away, etc. (I'm not good at those things!) I have an engine and gearbox coming this weekend to rebuild and having no open flat surface to work on it, it was cleanup day. While doing that I had one of those weird moments: "What is that and where did it come from?"

On a shelf loosely wrapped in plastic was the head in the picture. I haven't taken the time to know even if it is 750 or 850, but it appears new. On the top is says CROSSE. Anyone know anything about this?

Nonsense Found Building Bikes
 
In this case, the nonsense is me!

Over the years I've bought out people retiring, dying, in money trouble, no longer interested in bikes, etc.

Once in a while I'm forced to straighten up, clean up, put away, etc. (I'm not good at those things!) I have an engine and gearbox coming this weekend to rebuild and having no open flat surface to work on it, it was cleanup day. While doing that I had one of those weird moments: "What is that and where did it come from?"

On a shelf loosely wrapped in plastic was the head in the picture. I haven't taken the time to know even if it is 750 or 850, but it appears new. On the top is says CROSSE. Anyone know anything about this?

View attachment 122645
Abbreviation for "MotoCrosse"?

Commando MX'er?
 
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