KDXRIDER.NET

First of all, hello. I'm new to the site. I picked up a 2001 KDX200 about two months ago. I've been going through the bike as it was fairly neglected in the past. At any rate, when I removed the flywheel and stator, I noticed a hard almost gasket type material to the left and right sides of the shaft. I didn't notice it initially as it was so dirty inside; only after I had cleaned it. Does anyone know if it came like this from the factory? If so, what's the purpose? If not, why would someone have put it there? While cleaning the area out, the right side practically fell off; so I took it off. Just looking, these do not appear to be providing any purpose. The shaft and seal seem fine, but it is bugging me before I put it back together. The bike was running fine with no noticeable problems before I started working on it. See links to pics below. Thanks for any help you can provide.

Thanks,
Chuck

https://flic.kr/p/2j1CgUU

https://flic.kr/p/2j1CkoC

https://flic.kr/p/2j1CkqG

https://flic.kr/p/2j1EYyo

Welcome to kdxrider.net. I regret to inform you that someone has removed the seal retaining portion of the left crankcase half. Someone chose to not do the job properly with the correct tools. That seal is designed to be retained by the design of the crankcase half. See the picture below from an eBay seller. The crankcase halves are supposed to be split, then the seal removed from behind. I assume the dots on there are punch marks to intend to push the metal in to help keep the seal from becoming loose. Hopefully, the caulk glob was not to seal a leak, if they ground away too much aluminum alloy.

Sorry that someone used such poor technique.

Wow. Never good when someone starts off with "I regret to inform you...". I really do appreciate your explanation and the picture so now I see what it 'should' look like, bad news as it is for me. Given what I have here, what do you suggest that I do (if anything)?

Thanks,
Chuck

You might want to clean it up and inspect it. The globs used may be J-B Weld. I would do one of the following:

1. clean it up, rough it up, reapply J-B Weld, ride it and hope for the best.

2. disassemble, buy a pair of used crankcase halves, new bearings, seals, bushings, etc.

Either way, please let the next owner know the situation. For example:

viewtopic.php?f=86&t=23643&p=208035&hilit=leave#p208035

Okay, thanks! I think I will pull off the old on the other side, and just try to clean it up all the way around and reseal it for now. If I use JB Weld, won't it stick to the seal and be hard to replace if someone ever wanted to?

Chuck

Man, don't you just hate it when someone buggers up an engine like that? I'm betting it took more work to do this than to split the cases and do the job right to begin with. Oh well. Were it mine, I would probably try the JB Weld route. If it doesn't work (and yes, it may well stick to the seal) you won't be out anything but your time and a package of JB Weld.

Ouch. I hate finding hacked up stuff on bikes. Your possible solutions have already been suggested but I will also suggest that you can possibly go the route Harold went on his. He did mod his cases to be able to remove the crank seals without splitting the cases but he put a lot of extra thought and work in to his. The links to his mods are in the thread that KDXGarage posted above but I'll post them here.

https://haroldbawlzangya.com/2015/12/03 ... the-cases/
https://haroldbawlzangya.com/2016/02/01 ... model-392/

Good luck with it!

Thanks guys for all the replies and help. Chuck

SS109 wrote: ↑04:10 pm May 13 2020 Ouch. I hate finding hacked up stuff on bikes. Your possible solutions have already been suggested but I will also suggest that you can possibly go the route Harold went on his. He did mod his cases to be able to remove the crank seals without splitting the cases but he put a lot of extra thought and work in to his. The links to his mods are in the thread that KDXGarage posted above but I'll post them here.

https://haroldbawlzangya.com/2015/12/03 ... the-cases/
https://haroldbawlzangya.com/2016/02/01 ... model-392/

Good luck with it!

That guy is very talented! Unfortunately, that level of work is out of my league. I'm going to put mine back together. I guess worst scenario is I find myself tearing it apart and replacing the side case if it ever develops a problem. You never know what you will find on old bikes until you take them apart. Who knows how many hands this bike has been through and they didn't even know this had been done. It seems this bike has not had any maintenance performed on it in forever. I'm a sucker for saving basket cases and I got a basket full this time.

Chuck

Never a good thing finding other peoples handiwork, looks like they used a genuine Suzuki seal too. Did they do the right side like this too? If you are going to use them this way, if you can't make up that plate you might try this. Clean the area best you can with a wire brush/sandpaper and contact cleaner(Brake) reapply the JB Weld along the seal/case and let it dry fully, you could then apply a thick layer of high temp silicone at areas on the stator that overlap the seal and install the stator plate sandwiching the sealant between the case and stator and allow it to cure, you could try gasket material sandwiched between the two also, this I think would at least keep the seal from popping out, make sure there is clearance for the inner hub of the flywheel, do your best with the JB Weld on the right side if it has been modified too. On Many engines the seals can be removed/installed from the outside, never really tested how much pressure is in a bottom end or what it would take to pop a seal.

James..

Good ideas!

Most of the last 20 years of KX125's, one could get the seal out on the left side without disassembly. Some other dirt bikes are indeed like that, but extremely few green ones.

In other bad news, I recently read that one way that seals can go bad is from a wobbly crankshaft which has worn out main bearings, allowing some play in the system. It would make me wonder if some jassack replaced the seals, but not the bearings, as replacing both is the "correct way".

Check for play on the shaft end.

JimmyB wrote: ↑03:17 pm May 14 2020 Never a good thing finding other peoples handiwork, looks like they used a genuine Suzuki seal too. Did they do the right side like this too?

James..

Looks like the clutch side has not been messed with. See pics below.

WHEW! Good!

KDXGarage wrote: ↑10:13 pm May 14 2020

Check for play on the shaft end.

Not sure what you mean by 'play', but I can't budge the flywheel shaft in any direction; feels very solid.

Yep, that is what I meant. That is good.

While going back through some pictures I'd taken while working on the bike (I take lots of pictures), I noticed a pic that I didn't remember that shows oil inside the stator cover. I looked at that today and thought, that shouldn't have oil in it. I know this would have been obvious to most if not all of you. It's no excuse but it was more dirty than oily when I took it off and looked. Wasn't focused on the inside of the cover at the time. Go ahead and say it, I'm a (insert whatever you like). At any rate, I wanted to confirm that's the only place this oil could have come from before I go any further. This is a huge setback for me as I now have put everything back together and now I'm looking at taking the whole motor apart to replace the left case. That means more time, education, tools, $$$, etc. I felt pretty good about what I'd already done (new piston/rings, disassembled power valve assembly, cleaned, and put back together, new clutch plates, new kickstart assembly, new flywheel (old one was badly corroded).

First time disassembling a 2-stroke, so need to educate myself on the bottom end.

Kind of depressing, I just want to go ride! 2 steps forward and 10 back!

Thanks,
Chuck

Oil there comes through the left side crank seal, it needs to be replaced. Good news is you can now pull it without opening the motor...

bufftester wrote: ↑08:35 pm Jun 29 2020 Oil there comes through the left side crank seal, it needs to be replaced. Good news is you can now pull it without opening the motor...

Would be nice to do that, but after chiseling off the 'seal lip holders' or whatever they are called, someone used a punch around the seal; you can see the punch marks in the last pic (I'm assuming to keep the seal in) but in the process they distorted the shape of the hole. So I don't know that I can remove the old seal and replace it in the shape it's in?

And that's a Suzuki seal they used (looks to be rubber only), not the OEM with the metal outer portion. Not even sure what it was from so have no idea what I would replace it with.

Yeah, the proper way to fix it would be to find a new set of case halves and move everything over, not cheap or quick tho.

bufftester wrote: ↑09:27 pm Jun 29 2020 Yeah, the proper way to fix it would be to find a new set of case halves and move everything over, not cheap or quick tho.

Can I not just replace the left side case? I got to get a set?