'73 400CR The journey begins....

[TexasMule]

Been looking for an MK Husky for many years. Finally found one in pretty decent shape.

So now the journey begins. It appears to me to be a very low hour bike. I pulled the head and it looked unbelievably clean.

That's after wiping the oil off with a paper towel.

I think it's the original piston. Standard bore is 81.50 and it's stamped 8142 ????? Not sure
what the 52/110 means.

Here's the piston before I cleaned it up for the photo. I used to race Huskys and this
is in better shape than after 3-4 races.

I have one last question for the evening. It appears someone may have performed a
LeFevre frame modification on the bike.

Because the gas tank doesn't fit over the rear bolt hole.

It's been a few (45) years since I worked on Huskys, thought maybe some of the experts
on this forum could help me out.

Thanks,
Bill

 

[TexasMule]

John does his modification BEHIND the rear tank bolt not in front like the goob did on my bike.

 

[Steve-F]

Yes, I have seen John's work and agree with TexasMule, John is only 10 miles from me

 

[TexasMule]

I'm not sure if I ever put up photos of the finished project. She turned out pretty well. I'm pleased.

 

[Crashaholic]

Very nice! Wouldn't mind having that in my garage, although it wouldn't be as clean. Curious if the frame mod improves turning ability (as stated on Johns site) enough to make it worth while. I'm not a motocross guy so I don't know how to turn anyways.

 

[TexasMule]

As I said in a previous post. John does his frame modification BEHIND the rear tank mount, not in front.

Someone else will have to chime in if the modification improves turning ability. I haven't raced/ridden this bike since I got it.

 

[Crashaholic]

Being curious about the frame mod I checked out LeFevres website and it looks like he doesn't cut the backbone, only the sub-frame where it meets the backbone. Then he makes two small bends in each of the two the sub-frame struts. Also looks like he makes a bend in the rear fender loop.

By cutting the backbone it looks like a different approach was used on your bike. Its interesting the different ideas implemented back in those days.

I remember seeing a motorcycle magazine article long ago of someone offering to turn an MJ or MK frame into a cantilever setup (i.e. lay down shocks).

 

[Picklito]

John's mod is simple and very effective. He did it on my 73 400CR. He moves the forward seat tubing up and forward (yellow arrow), which creates a slight bend in the seat stay tube (blue circles).

 

[Picklito]

It creates a much flatter seat profile and allows you to get forward more easily. It works.
Yes, I know this is the wrong tank! This was the mock up.

 

[Crashaholic]

It creates a much flatter seat profile and allows you to get forward more easily.

Wouldn't a flat seat, vs a forward slanted one, help with staying on the rear of the seat will less effort. From a grumpy old desert racers perspective, that would help reduce fatigue in a 100mile H&H.

 

[Picklito]

Hey Crash, I get what you're saying. I feel it makes the seat tank transition much flatter. I actually sit right on the back of that tank in some corners. It was harder to do that before the mod.