Smitherz

FLIP IT & run it. Just remember the tires condition when you are hard charging. You'll eventually ride according to the tires performance. I run pretty fast so if it were mine I would just throw another one on if I was riding with a crowd. :- ] Just do some sport riding and don't go riskin your skin this time.

The powervalve assembly is extremely unique to that engine. You can't swap anything else but an OEM one to that engine. Where abouts are you from?

I had a CR250 back in the day and it went WIDE open when I was at about 85% throttle. I just ignored it and kept riding. I used to ride this sucker at LEAST every other day back then. It did this maybe 2 other times over the course of a month and then never again. I never found out what it was and I didn't care. It was definitely kinda scary but I was able to control it every time. I would just pull in the clutch and snap the throttle once or twice. =] If I was to guess I would say it was a tiny piece of sand that might have worked past the air filter. I was very poor back then in my teens and I couldn't afford to do anything but clean the bike. I probably could have used a new air filter. Clean sticky air filters are so so important. About the crank seals... They aren't too hard to replace and VERY good piece of mind to have new ones in there. I recommend everyone replace them in their older 2 strokes, especially if you don't know the complete history of the bike. I've solved problems with a couple bikes in the last year because of leaking crank seals. Usually people have problems with them running crappy and they start by trying to buy things like new carbs before they are warned that it is more likely to be the seals. I would just check over everything here that has been discussed and then go ride some more. Obviously stay away from the big jumps for a little while! But see if the bike does it again before spending a bunch of money chasing the problem. Like Cham said - check to make sure the carb boots are tight and the reed block while you're at it. Sweet ride.

WHAT REAR tire is this?? =o Does anyone know?

Another overlooked item... the cam chain. Many people will just re-use them when rebuilding and they get worse and worse. The old Yamahas run so much better with a new cam chain.... mine did/ Starting was much easier and it sounded a LOT healthier as well.

Awesome! Sounds like you found the right shop. I didn't know it was a KTM dealer... they better know what's up! Good good. That's their cost on the can of the Maxima as well... I would ask for a case at that price! : ) Check out Maxima SC1 too. I always have a can on hand... people buy it purely because it smells so good even. Mismatched rear caliper? Was it on the bike and working when you took it in? Isn't it a Brembo like it came with? Take a picture for us here so we can see. - I wish I could just throw down for a new 300 haha someday...

Hello - Two hours for both the shock and forks? A good suspension dude could do the rear shock and the forks both in 2 hours yes. I've seen people take 2 hours to do just the forks - phone interruptions, or they drop parts on the ground or forget what parts go where... this can KILL your work time. This work can go by SO fast with experience and proper tool organization. CHECK YOUR CLICKER POSITIONS on your forks and shock. See if they work first by making sure the hard settings make the shock slow and the soft settings allow the suspension to move fast. Then when you get the suspension back you can see the difference. Write it down before you take your bike apart and take notes of the position your clamps are on your forks and where the rear spring adjustment collar is on the shock body. Heck, take pictures. Make sure they are off the bike and nice and as clean as you can get them. The less they have to deal with cleaning the more time they have to do the actual work - without contamination. And when you bring things in to have worked on, when they are clean they know that you took the time and actually care about your bike. People usually inspect while cleaning. I recommend you do such and take pictures of the forks and shock before you take them in. Some shops will just toss them up on the bench, not knowing any better (the helper or shop monkey, usually not the guy doing the actual work). They should treat the machine better as you have better standards with your cleaned up parts. Just to point out a few things involved - ask them to clean out the old oil with solvents, preferably Maxima Suspension Clean, and I would offer to buy them a new can by having them add it to the invoice. It's worth every penny to have all that old nasty oil cleaned out. That generation of forks is much easier to clean out & they are VERY simple inside compared to the KYB/ Showa style. It shouldn't be a big deal for them to do a good cleaning which is just using up a good portion of that Maxima can to spray all the bad away. That Maxima Suspension Clean is the BEST stuff for the job, smells good and won't make you pass out from fumes. Give them the ok to use the better brands of seals and Racetech components and you'll be golden. INSIST they don't use the cheap stuff as we discussed. I would actually prefer they save the wrappers for the new components they use during the job. Don't laugh. I've been burned before. All the high quality seals, oils, bumps stops, shock bladders they need can be had in 2 or 3 days so it's not a big deal for them to order them up. You can go on Race Techs website and check all the parts and about how much they cost - even order them up and take them in with you. Just be extra careful to order the correct parts for sure... nothing worse than having to pay the shop and then finding out the parts are the wrong part # or something... that's a big mess. REAR SHOCK: If your bump stop for the rear shock looks beat up GET A NEW ONE. I know they are 30-$40 but now is the only time you'll have to replace it and they are important. Check where they will need to charge up your rear shock with nitrogen. Does it have a Schrader valve on it so it's nice and easy to charge up? The older ones require a needle and are a pain and can fail with age. Hopefully you have a regular Schradar and if you don't I highly recommend you have a Race Tech bladder cap kit put in. You want the suspension to work as good as possible and holding all the charge and oils in like new. I know this can add up but it's worth it IF you are going to keep the bike and get the maximum value for your ride time. FORKS: Bushings wear out and when they do they will trash the fork tubes as the slide up and down. Bushings are NOT that expensive and are SUPER easy to change out. I insist you have them done for piece of mind and performance. They older forks can work very well IF they are brought back to "new" standards. If they are worn out your old forks will FEEL old and slow no matter what. It's a great bang for the buck maintenance thing that many shops don't recommend for some reason. Lots of shops just drain oil, pop in new seals, fill it up and send you out the door. Don't forget to request that solvent flush. Adding the suspension cleaning might stack on a little more time like a half hour possibly... and if you give them a few more parts to replace then I would expect this as well. It's acceptable. Flushing and multiple rinses take a little time. Unpackaging more parts and making sure everything is groovy take a little time. Your bike will be very happy if you replaced all these parts. I know it adds up but just save up a bit because it's worth it and your bike will be worth more money. Save the receipts for proof and records!! MAKE SURE YOU CHECK THE CLICKERS WHEN YOU REINSTALL YOUR SUSPENSION. Make SURE that at the weakest settings the suspension works like it should... then turn everything to the hardest setting and check again. Pay attention here - if they DO NOT work like you expect then something could be wrong and I would discuss it with the shop. Then put it back where you started (or recommended from the manual) and go from there on your first ride to try it out. This is just from my experience with many bikes that I own and restore for fun and race here and there at the intermediate level. I've been paid to build bikes, street and dirt, and setup bikes and suspension as well. I have a soft spot for KTMs new and old... the PDS suspension is a subject I really enjoy. =] I'm here to help not sell products or offend anyone.

Oh and if you can press on the seat hard and it goes down and just bounces back up... the seal has failed and it has lost the gas charge. Use HIGH QUALITY seals. I lost a seal once and had it replaced (by a shop that insisted on cheaper brand) and it failed after 15 minutes. I was NOT happy. Then I told them to buy the best brand (SKF if I can recall) they could get and no problems since. I have a friend with a 2004 450 with PDS and his rear seal failed as well. It happens.

I would highly recommend a service if you don't know if it's been done before. I've taken more and more shocks apart lately to find horrible oil inside them. It wears down the shock bodies quickly when it's dirty and the only fix is a new one. I would only send a shock body for a coating if it was in very good shape - not for purpose of repair. Just my opinion. Use the highest quality shock components for servicing. Don't buy cheap seals etc. I have a couple PDS bikes and they are indeed more bouncy and are for offroad riding not racing from the factory (talking older generation). As long as you can dial them down so they don't spit you in the air on big impacts you should be fine. Then you know they are not set up for you. Like when you are going up a hill and you hit a big bump in the surface or rock... it should try and soak it up. If you find yourself up off the seat as a result adjust it and if that doesn't work I would have it rebuilt for longevity and safety. Get it back to good working condition and stock settings to evaluate how you like it - before you just ask for new valving or a new spring. You can have them setup for racing (or more aggressive high speed action) but make sure you send it to a suspension guy with experience with the PDS. They also require more sag than regular guys are used to!

The hard compound lasts a LONG time - agreed. They are a little on the heavy side but they last. I actually cut the leading edges sharp before heading out last weekend on my CR250. With the new sharp edges they gave more bite for sure. Instead of tossing the half worn down and rounded edge 360... the sharpening proved good enough for a couple more rides easily. It takes less time to sharpen the edges of the center row than it does to change it. ✊⚡

Light hone / properly sized piston and ring. Easy. I would smooth down a couple of those rough edges on the ports... but lets not get into that here. =] You could send the cylinder to a pro and have him spend an hour sizing things up, getting a proper piston and maybe a little cylinder magic. It would make that thing sing like it was meant to. And be worth every penny.

They will both work good. Get the one that fits best that will make your ride more comfortable etc etc. I have a few, I ride hard and roll with Arai because of the crazy speeds we do out there. I actually landed so hard flying off of a mountain that when I landed I KNEW that the helmet was DONE. It was amazed how well it took the impact and saved my bacon. It was a couple years old so I tossed that Arai in the trash with a tear. I use Suomy (lightest & ECE rated) for easy riding or slow speed technical. I have two Arai for the dirty work. I am not rich but you gotta preserve your head man. I have nothing against Bell though... they are a great helmet and I see off-road racers in them all the time. I've talked to Bell employees and they love their job and work very hard to improve their products. Troy Lee just puts their name on a cool looking helmet to sell them imo. The helmet I tossed is pictured in my avatar here... I miss that paint job!!

Ahh crap, loose piston action... yuck now what? Measure that bore and order a piston kit accordingly? That's always fun. At least it's not damaged!

Normal color typical for aftermarket cranks imo. I would take it to a shop and just ask them about the play - side to side / vertical etc. They see it all there. Probably ask them what type of beer they like to drink first and then what they think of the crank. Then come back with the beer for em. Then the next time you have a question while rebuilding something they will be more than willing to help you out. There is a LOT moving around in that engine so check your cam journals, your clutch assembly clearances... toss the timing chain!!! get a new one right now - they are cheap. I solved a couple problems in an old WR426 I restored by replacing the t-chain. Double check the chain guides in there... or that they are even in there. I've seen nightmares come into my friends shop recently. People have been pulling out super old dirt bikes and just making them fire up to put on the market since there seems to be shortage of bikes right now. Guess what? They're all worn out! haha. A friend of mine bought an 04 CR450F that was offroad raced... but the guy swore that the engine was "just all rebuilt" when it was parked a year ago and he decided he was done riding. Yeah right. My friend got completely ripped off. So yeah, lots of people rebuild engines like yours and just run that chain again because they think they last forever or they forget to order another one. 9 times out of 10 when you ask the local mechanic what he thinks he'll just tell you to run it again. Wrongo. I got one for my 426 from Ebay - YBN brand which I could only find good feedback on - 30 bucks and will only help your bike. I also put a pair of HotCams in the bike which made a HUGE difference in starting up, and power in every way. Highly recommend.

Try that gauge out on another engine just to check it just for sport. It's probably good but I don't trust digital gauges at all for higher PSI. I would just replace the crank seals while you are working on it. Easy stuff and the perfect time to just get it all over with. Also inspect the dome of the piston VERY closely to the one you are swapping out. I've seen super cheap ones that don't have as much material on top which results in ... lower psi of course. Not long ago a friend of mine ball-honed his own cylinder (vintage bike) out and completely ruined it! It cost him much more to have it repaired once he was done with his work haha. The machinist called it a bell curve cylinder due to him honing the crap out of it to "remove" scoring in the cylinder in order to make it look pretty. He would have been better off just using steel wool and putting everything back together. 😄 Just a warning to people - ball-hones are dangerous in the hands of the untrained. They shouldn't be used on modern bikes at all IMO - especially a no-no on plated cylinders.