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KTM Thumper Discussion

Perhaps under 36 for the 690 super moto. My 690R is like stepping over a yard stick. I think it specs at 36.6 high. :eek2: I bought it sight unseen. I had only looked at an 08, which the seat height is listed at 35.5. The suspension travel was increased for 09 and that made it an inch taller. Needless to say I was surprised when I walked into the showroom. But I've changed my riding style so it does not bother me too much. Except when offroad and you stop over a low area. (See Bastrop Ride Video) :haha: Once it starts to go over, it's over. :pound: But otherwise it is So Much Fun, :flip: that I have never regretted buying it.
 
I just wanted to share this with any of you guys out there with a 690, I ordered on of Ice Man Jacks case protectors last week and have to tell everybody that this is one fine made part. Thanks jack it really is good looking and fit perfectly.
I will have to try later to upload a picture, it keeps saying it failed:doh::giveup:
 
I just wanted to share this with any of you guys out there with a 690, I ordered on of Ice Man Jacks case protectors last week and have to tell everybody that this is one fine made part. Thanks jack it really is good looking and fit perfectly.
I will have to try later to upload a picture, it keeps saying it failed:doh::giveup:

If you are trying to do an attachment, check the size of the image you are trying to upload. they have to be 640 X 480 or smaller and I think around 190KB or smaller. If they are larger you get a timeout error.
 
That'll teach me to check my valves more often...

Doing some maintenance/cleanup today so I pull off the tank for the first time in quite awhile. Low and behold, the breather line that goes into the valve cover wasn't on... oily dirt everywhere. The big breather line was wide open, meaning there was a direct dirt-injection path back into the intake side of my carb and into the crankcase (since KTM routes all that crap together). Not to mention underneath the valve cover.

The last time the valves were checked and that cover pulled off were back in August when I had it in the shop to have some other work done. Given how stiff those breather lines are and the fact that there's essentially no relative motion between the components, I don' think that line was ever replaced. Last August. 7 - 8 mostly dusty months back. :angryfire:angryfire:angryfire

Now I get to pull and clean the carb GRRRRRRR.....

So, any reason not to just route that valve cover breather to a small filter and cap the other two holes (1x into the carb and 1x into the crank case)? Sam were we talking about this last time you came out to help me de-smog?

J
 
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Hood Ornament, your pics and write up were most helpful. I did fork seals the other night and it went off without a hitch.
I didn't have the numbers for the oil level, so I measured both and they were different. I ended up putting the same amount in both, using a full liter.

I'm installing my damper this week too.
 
Well, how was the race? I need details!

Well if I remember correctly, I had told you about some people taking the vent off the air intake boot. They would buy two filter vents, usually from a bike shop or Summit racing or Jegs. Then route the trans and valve cover vent up under the tank and install the vent filter in each hose. Some people ran the vent hoses to a tee under the tank and then just one filter. Something like this.

http://www.summitracing.com/parts/KNN-62-1090/?rtype=10

You should be able to find this somewhere local.

Most people do this to stop the oil ingestion from the valve cover to the intake. I fixed Shirley's by installing a restrictor at the intake boot. But that's not your problem, you want to keep the hoses from coming off. Even if you put a separate vent on, you have to secure the hoses either with an adhesive or hose clamp. But I agree with you, they probably were not put back on.

Check out your intake area and get whatever grit out that you can. Also drain the trans fluid. I would refill it and after the next ride drain it again, just to flush as much grit out as possible. Remember to use a trans fluid, not normal engine oil.
Let me know if you have any other questions. If I have not muddied the water enough. :trust:
Sam
 
Sam that's exactly what I thought we'd talked about, just couldn't remember if it had actually happened or if I'd imagined it. Can't believe I ran the bike for months with that wide open :doh::giveup:

Trans fluid was just drained before the Desert 100, and every 500 miles before that.

Is this worth a thorough carb cleaning or am I just asking for more trouble? If it is, does anybody have any helpful hints for getting the carb out of a 2008 (post-RFS) KTM 450 EXC? Man it looks tight...

Speaking of the Desert 100, here's a quick RR I did. I was going to reciprocate on TWT but haven't had the chance. It was an eye-opener, that's for sure... next year if I'm still around I'd be tempted to find a guy to tag-team the race with, they'll let you do 2-man teams. I wish I had a shot of the mud in camp and I'd probably revise my estimate to 6,000 - 8,000 people due to the rain.

Post #460 on Page 19...
 
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I only brought up the trans because it's the lowest hose and dirt will migrate down the hose. No one needs trans problems!
There is a discussion about pulling the carb a few pages back. If you find dirt in your air intake, it will be on your slide, in your float bowl and the intake track in the head.
I would loosen the carb to air boot clamp, remove the 2 lowest subframe bolts, raise the subframe and use a bungie to tie it up. Then the carb is easy to get off, and look down the intake to see how much gunk my have infiltrated. Only you can make the choice of going any further. Dirt is bad on valves and rings.
Also you may want to remove your valve cover just to see if anything is in there. Don't forget to wash out the hoses if you are going to reuse them.

Love the race report. Sounds like you got your money's worth. I guess you were riding a dual sport class. But in a race, if they are going to have a sweep crew, you should only take a minimum of tools and spares. I only carry a spark plug and a master link along with my tools. Anything more is weight. Whether on your back or on the bike you still have to muscle it around. If you have to change a flat you have lost the race with that 10 minutes anyway. Now if they don't have a sweep crew, then it is up to you to get back to camp! :ponder:

Good luck with your checks. Sam
 
Popped the sub-frame and yanked the carb tonight... intake side was gritty and dirty. Top of the carb where the slide goes looked like mud up there... can't believe the bike ran as well as it did :giveup:
 
Great report on the race! Thanks for taking us along.

Justin, tear that carb down to the itty bitty pieces and clean it. These fcr carbs are a miracle when well and a real pain when they ain't. If it takes an entire can of carb cleaner to blow out all the crud then so be it. Exploded diagrams are all over the web for them and the cleaning part is way easier than getting the dang carb off the bike. Just be sure the text on your pump diaphram is pointing out when you go back together with it (don't ask how I know this is important).

Whatever got into the valves and cylinder probably got blown out. All that grit sticking to the greasy inside walls on the manifold tube (tween the carb and head) is what bothers me. It'll just keep feeding grit to the engine if left there. Pulling it with the carb already out of the way should be easy (don't know - I've never done it). Let us know how it goes.
 
Perhaps something like a gun cleaning rod. A tee shirt on a cloths hanger, some type of liquid cleaner, and some gentle scubbing. Just not sure how much the rings and valves may have ingested already. But if it is not smoking or the valve adjustment has not changed, maybe it has been caught before any damage. If there is that much in the carb, I would pull the valve cover and check in there.
Sorry to be such a downer after your ride weekend.
But it was a great report, and I wish I had been with you. You made it sound like a great event. :clap: Sam
 
That is a pretty common problem with the FCR.... I believe slavens has a cure for it. A little filter box that has mulitple ins and outs.

http://slavensracing.com/products/carburetor/carburetor-vent-filter-by-7602

Just did the piston on mine (450exc with 350 hrs on it). Nothing in the valve cover. If anything it would go strait to the cyclinder.

Interesting, but that filter cover is designed for the vent lines, much smaller diameter than the valve cover breather and kind of in the wrong location.

So in other news, have any of you guys seen a replacement for these (#3 and #4). They will be the death of me...
Subframe-Insert.jpg
 
No and I have never noticed them. Does something bolt into them? I could go out to the garage and look but since you asked... Have you lost them before?

And as for the Slavens thing, your problem was not with dust going up the hoses, it was a major hose was left off. :miffed: Which, in turn, left you hosed! :moon: Sam

p.s. I am on the way to the garage to look. :brainsnap
 
No and I have never noticed them. Does something bolt into them? I could go out to the garage and look but since you asked... Have you lost them before?

And as for the Slavens thing, your problem was not with dust going up the hoses, it was a major hose was left off. :miffed: Which, in turn, left you hosed! :moon: Sam

p.s. I am on the way to the garage to look. :brainsnap

Yeah my subfender attaches to them with #33...
Rear-Fender-2.jpg


They're little molded rubber thingy's with a metallic insert, into which you screw this strange drywall looking screw (#33). A crappy design, very little "feel" for when it's tight, and the screw eventually (at least in my case) tears up the insert and can bind or gall itself solid with the darned thing.
 
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I have met the enemy and the enemy is mine.... RTV'd in two 6 mm 316 SS nylock nuts and they worked like a charm.
 
I went out to the garage and still could not see them. What happens to them, missing or stripped? Sam
 
KTM gurus. While riding today (did the MX school) the bike was getting harder to start the later it got.
Is it time for rings and valve check?
AFAIK it's on the original wings and two years ago the vales were in spec.
 
I want a bike with wings. I would fly around the vale.
 
I went out to the garage and still could not see them. What happens to them, missing or stripped? Sam

Sam, since the screws that go in are nominally self-threading screws, they eventually gall/strip everything out.

Got the front wheel bearings and seals in this afternoon, walked around Ace Hardware with a pair of dial calipers until I found a PVC fitting that had the perfect diameter to press them in. Only a little drama with one bearing that didn't want to fully seat. So KTM is finally alive and running well but man what a struggle. Forgot to mention, the first thing I did when gaining access to the carb was pop the subframe loose and lift it... and the first 8mm screw I backed out basically jammed up with Loctite and trashed the threads in the hole. GRRRR.... had to go buy a tap and chase them. Second thing I did was tie the subframe out of the way with bungie cords up over my garage door track. Of course 30 minutes later I'm coming in from outside and pop the garage door only to watch it rip the bike off the stand and dump it on the floor (the front wheel was off as well). I couldn't win for losin.

J
 
KTM gurus. While riding today (did the MX school) the bike was getting harder to start the later it got.
Is it time for rings and valve check?
AFAIK it's on the original wings and two years ago the vales were in spec.

I'm far from a guru, but the things that pop into mind are A) is it desmogged? and B) valves.

J
 
It never was smogged :mrgreen: its a 250sxf.
Though I did recently put a can with a spark arrester in it.
I'll do the valves in the next week or so.
 
I would bet the valves are in spec. They hardly ever go out. However, they may not be sealing. Do a leak down. Air filter clean?
 
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