Boring KTM Rebuild Thread

[El Camexican]

Very cool tip. I just learned something new!

As someone who considers them self the Forrest Gump of mechanics I am once again honored.

[HairyJR]

Always enjoy reading your build threads. It amazes me how you complete a certain task sometimes with the limited tools available, a backyard mechanic at heart.

.......As far as some of the goofy detail in this thread, I’m one of what must be thousands of people that feel cheated when watching a show like American Chopper, or Overhauling and see them jump from start to finish with no one busting a knuckle......

I agree with you, it's the little things an average joe watching wants to see, "how too tips" , can go to car shows to see pretty things.

"HJ"

[Maico]

Once I read the words "gravitational intervention" in your first post, I was hooked! You think that KTM is a peckered knob, try restoring a '92 KTM 550 DXC. Parts are available...just not the ones you need.

[El Camexican]

You think that KTM is a peckered knob, try restoring a '92 KTM 550 DXC. Parts are available...just not the ones you need.

I can’t even imagine. Can you still get pistons and rods for those?

The first thing I say when somebody asks me about buying a used KTM is “Don’t even look at anything older than 2004” but I should probably upgrade and start saying 2009.

Speaking of old, on Monday I met the guy who sold my KTM’s bikes to the public when new in 2002 & 2003. He let the dealership go in 2007 and sells Yamaha’s now. The guy is like 60 and still rides a TZ250 on track days.

[El Camexican]

Welcome back to another fun filled weekend at Nico’s place boys and girls.

We’re starting off a little late today due to the effects of some over consumption by your host, but be assured, the Advils have kicked in and we’re feeling good enough to start thinking about a 5:00pm cocktail.

We begin today’s adventure by cleaning, straightening and installing the skid plate onto the donor frame.

First we remove as much of the spooge as possible with a woodworking tool that was bought with the best intentions yet has somehow made it into our motorcycle toolbox.



We then follow up with a chemical cleaning using some old pre-mix we happen to have laying around and then beat and bend the part back into its original shape.





The sound of aluminum sheet metal being beaten on the concrete floor really tests the strength of the Advil.

[El Camexican]

Next we cut strips of rubber from an old tire tube to use as insulators for the skid plate. While this is a great way to protect the paint, it’s also fantastic for reducing the amount of noise generated by a rock hitting the aluminum plate, which has been known to scare the living **** out of this guy when it happens unexpectedly.



The easiest way to do this is to wrap the rubber approximately 1.5 times around the diameter of the tube and then put a wrap of electrical tape around it to hold it in place, but still allow it to be moved back-and-forth to avoid the mounting hardware when mounting the skid plate to the frame.

The rubber also acts as a bit of a lock washer in that it pretensions the bolts which are only holding a flimsy piece of sheet metal and can otherwise vibrate loose. I highly recommend Loctite on these threads, but that means doing a very thorough job of cleaning the threads as there is a lot of oil in this area.

[El Camexican]

And there we have it.

[El Camexican]

A few years ago I polished the triple clamps on this bike only to find out on the inaugural ride that the lower clamp was bent. I was so upset with myself for having gone through the effort of polishing it that I refused to polish the replacement that I bought on eBay until I had proven to myself that it was not tweaked. That was a few years ago and this will be the first time that I’ve had it off the bike, so I’m going to take the opportunity to polish it before putting it back on.

Because the forks have been recently anodized I don’t want to scratch them, so I removed the bolts and drove wedges into the clamps to open them up for easy removal.



This is what I want it to look like when I’m done.



I use duct tape to protect the bearing rather than remove it which is a fairly arduous task.

[El Camexican]

We begin with removing the forging flash with grinders.



Next we wet sand graduating from 220 to 1500



And finally we hit the part with a buffer and wipe it clean



It’s always a good idea to scuff all of the edges that make contact with your forks to avoid scratching. I usually do this with the 320 grit sandpaper, but you can also use small tungsten files

[El Camexican]

Before putting the triple tree back onto the forks and inserting the stem into the frame the bearing must be greased. You can’t over grease this area, especially up at the top where the water would get into it should it enter from the top of the tree.



Always use anti-seize before inserting steel bolts into the aluminum triple tree. Because there is a spring like tension on these bolts they cannot come loose. In fact their torque recommendations are very low, something in the neighborhood of 11 and 14 foot pounds. Anything more than this and you can damage your fork tubes.



Now we are ready to put the motor in but even though this particular engine has less than 20 hours on it I want to pull the head off and inspect it for a number of reasons. The first being that it was run with the muffler off the spigot for a period of time and I was concerned that some dust may have gotten sucked into the engine, but looking through the exhaust port everything seems nice and fresh.



The other reason I want to remove the top end is because I suspect that even though the squish band on this engine is almost .035” tighter than stock, it could still be a little tighter. I can feel the difference between this engine and the other one at low rpm. Currently this engine has a squish of .058”.



This engine also has a sleeve in it, and it hasn’t been properly matched, so now that I have the correct porting tools I’m going to do it right.

[bkm]

Aound here there's gold in them there KTM's. That's the only explanation for the price people try to get out of them.

10-15 year old bikes guys are still trying to get 3k for them. And they're not nice either.

[El Camexican]

Today started with all the best intentions of turning our project into a roller, but due to unconsidered circumstances it seems this project has come to a grinding halt.

Apparently there is a difference between the EXC and SX frames and that is the provision for mounting a kickstand.



Note the missing mount



Well f**k me runnin, this certainly casts a cloud over our weekend, but when the KTM Gods shove oranges up yer arse, you make orange juice.

This frame will now be stripped down again and be used on the trike build and we will prep the original frame for this one.

One it is completed we will return to our regularly scheduled programing.

[schlepp29]

Man that things gonna be sweet when it's done.

[schlepp29]

Not to be a dumb arse but could you weld up your own stand mount? That thing is to good.

[El Camexican]

Not to be a dumb arse but could you weld up your own stand mount? That thing is to good.

Could, but it would mess up the paint. Was thinking of making the trike frame orange, so fate has determined that it will be.

Update - KTM lists part# 5470300140096 for all 2000 thru 2003 250/300 EXC, MXC and SX frames. Even lists a stand for the SX

And there is no sign the tab was cut off. Weird.