1989 KTM 125 MX Project

[j.concepcion54321]

Hey guys,

Just picked up this 1989 KTM 125 mx yesterday for 50 bucks. Thing is its completely taken apart. So far these are the parts that ive been able to make out...
-Entire Front end
-wheels(like new tread on them)
-engine in pieces in a box
-clutch(missing 2 springs)
-frame
-Subframe
-swingarm
-shock
-misc bolts and levers and shifters
-front and back brake
-sprockets
-tank with shrouds
-seat
-front and back fenders
-and a ton of other small stuff.

The ad on the internet said that all it was missing was the exhaust and he originally wanted 200. This was when he told me that everything was sorted in boxes in his shed.... That wasnt the case . Either way i am now realizing that i have my work cut out for me. The engine seems to me like a hopeless case. Im hoping that later this week i can get some work done on it and get it into a rolling chassis. Then i can continue to check out the engine. The flywheel/magneto area is pretty rusty, but still magnetic so its still good. The internal gears on the engine all seem to be in good shape and not rusted. The piston, connecting rod move freely but the engine doesnt turn over when i turn the flywheel. it jiggles a little bit but thats it. Is it supposed to do that or is it seized?

I know its kinda hard for you guys to get a feel for my project without pics but its been raining the past few days so when that clears up ill try to get some pics posted. In the meantime im hoping someone can answer some of the questions i had above and maybe some of you members from australia (where ktm bikes are from) might have some parts that i need or a shop manual.

 

[Kaptain Krunch]

Sounds like your crank bearings may be seized. or something is thats for sure. How torn apart is the motor? got any pics?

 

[j.concepcion54321]

Ill get some up tomorrow. I was planning on making it nice, but seeing all thats missing i may just try to get it running and use it as a beater bike. Either that or go the expensive route and try to source a new engine, or get this one rebuilt...

Quick question, i only saw 3 of the clutch springs, can i just use it with these 3 or do i need all 5?

 

[Kaptain Krunch]

I would get all 5, may not grab very good with only 3. You might have trouble finding parts for that bike. My buddy had a 91 ktm 250 and couldnt find anything for it at all. I have a few of the parts from his old motor he gave me that might work for yours, i have a clutch with springs if its the same style, and a few electrical parts.

 

[j.concepcion54321]

Alright guys, finally got some time to work on the bike and grab some pics. I made an album on photobucket for the bike with descriptions cause it was easier that way. Check it out here
http://s1205.beta.photobucket.com/user/theconcept9596/library/1989 KTM 125 MX
So yeah lemme know what you guys think so far,

QUESTIONS:
1- is that bottom end seized? it looks a little rusty but can be cleaned up.
2- is the top of the piston supposed to look like that? Im thinking yes because the inside of the head looks like that aswell.
3- Are there any parts that you can see are missing? lol
4-am i gonna have to keep taking apart the engine to clean it or is it fine as is?
5- iin connection with 2, am i gonna need to use a new piston and crank? or should these be fine?
6- am i correct in assuming that just cause the flywheel is magnetic its still good? i have the coil aswell and i think a good 95percent of the engine parts.

Ill have more along the way and more pics aswell. For now please take a look at the album and help me out with any of the questions. thanks.

@Kaptain Krunch- im sure that itll fit, i think the only thing different with those engines is the bore and stroke, most of the physical is the same so the clutch should work. How much would you want for those parts that you have? Hopefully not much so you can help a brother out

 

[Kaptain Krunch]

I wouldnt want much for the clutch, $10 + ship or something. However, that motor may not be worth it. Judging from the rust on the con-rod big end, and all the dirt, plus the lack of rags to keep stuff out of the tranny/crankcase i would say the bottom end is indeed seized, and even if it werent i would still tear it down and do every bearing, along with new piston and rings and all gaskets/seals, and maybe even a con rod.

Also, the cases look pretty mashed where the intake boot bolts on, did someone try to port it? also appears that the cases have been split slightly? Personally that is a job i would not bother tackling. But i hate basket case motors, so i may not be the one to talk to.

As far as the flywheel, as long as its magnetic and has no cracks or visible damage its ok. Crank should be fine, but like i said bearings seals the whole 9 yards.

 

[j.concepcion54321]

However, that motor may not be worth it. Judging from the rust on the con-rod big end, and all the dirt, plus the lack of rags to keep stuff out of the tranny/crankcase i would say the bottom end is indeed seized, and even if it werent i would still tear it down and do every bearing, along with new piston and rings and all gaskets/seals, and maybe even a con rod.

Sounds expensive to fix. So if i can just take it apart more, clean up those parts, and find a way to put it together should it still run? Because i cant seem to find any rebuild parts online. If i could find a rebuild kit then id go for it, i figure since its a foreign bike its gotta be worth more than 6 or 7 hundred

 

[Kaptain Krunch]

Yeah, fixing basket case motors the right way is never cheap. You can give it a shot, not gonna hurt anything to try to run it as is. may not last long, any vacuum leaks on a 2 stroke = death. If i were you i'd tear everything down and check it out, see where you stand. I've had suzuki bike motors with crank bearings with 1/8" of play, and 80lbs of compression that still ran. However, all of this also depends on the original reason it was taken apart.

As far as value. If that bike was mint, it would be worth 800 in my area...max

 

[j.concepcion54321]

Ok well I think I can get it running, but its dsf gonna need a bpttom and top end rebuild. The xonnecting rod has some play from left to right so that means the bearings are loose. I could try and source a new engine or just try to get it all together and sell it as a nonrunning project bike. That way I just make some cash and biut another bike.

 

[j.concepcion54321]

Hey guys, soo its been a while since ive posted but thats because i was on vacation in the Dominican Republic for around 20 days. It was nice i missed 2 weeks of school and i missed 2 snowstorms so i came back nice and warm and tan



Ok getting back on task, i have the bike in a rolling frame right now. Ill post a pic of it tomorrow after i get some hw done. All i can do at this point is wait because my parents wont let me work on it till all my school work is caught up. So my plan is to mount up the fenders and the seat and see how everything fits.

This is an mx bike, but the fender that he gave me for the rear has a light on it and it doesnt say ktm anywhere so im guessing its not stock. I have a cr125 rear fender that i might try to get to fit instead because it might look better.

Ive also been looking into buying a newer bike with a complete engine assembly. Like a cr125, and rm125, a kx125, etc. thats missing the front end and the rear end, just the frame with the engine, exhaust, good seat and plastics. then fabbing it up to my bike. That way i have the core of an older mx bike with the drivetrain and look of a newer normal style bike.

im now thinking the best option is to just turn this into a restomod, rather than a traditional restore...

 

[realfast89gt]

It is probably not real easy to find info on that thing. We had an 87 kx125 which we dismantled and installed the engine on a manco dingo..... we didnt find much info on it to get the bike working again, so we cut it up!!

 

[Bluethunder3320]

it looks like you're at the beginning of the same project ive been on since july. i picked up a 92 yz 125 (free) which had been seized, torn apart and missing a lot. the bottom end was really tight, and the top end was destroyed from pieces of the con rod bearing.

im at around 800 bucks into the project and just today found out that my engine wont run after putting in a reman crank, oversize piston& bored cyl, crank bearings, full gasket and seal kit, LOTS of expensive hardware, helicoils, new CDI box, and hours and hours of work.

if i could go back to july i would have just saved up and bought a running bike instead of what i thought would be the cheaper route, of fixing up an old bike. now after $800 i dont know if the bike will ever run. if i parted it out, i wouldnt get back near as much as what i put into it.

also its been very hard to find parts for my '92. and its only going to get harder. i cannot get certain parts like crankshafts and water hoses.

its a hard decision to either run away while you can, or dump hundreds of dollars into it and hope that it'll run.

EDIT: did some searching for a crankshaft and couldnt find any.

you can still get a wiseco rod and have a machinist remanufacture the old crankshaft. this is what i did, but someone i knew did it for me. there are places you can send your old crank and they'll do it.

you need a press to seperate the crank halves, press in the new pin, and balance each half almost perfectly. it was a lot of work. this is assuming the rest of the crankshaft is still good.

heres a link to the wiseco rod, only place i could find it is ebay.
http://www.ebay.com/itm/31047307553...ries&cmd=ViewItem&hash=item4849a32b4f&vxp=mtr

if you decide to rebuild this bike i strongly recommend buying a manual. the torque specs are very important on these, and itll show you how to do everything right.

 

[j.concepcion54321]

it looks like you're at the beginning of the same project ive been on since july. i picked up a 92 yz 125 (free) which had been seized, torn apart and missing a lot. the bottom end was really tight, and the top end was destroyed from pieces of the con rod bearing.

im at around 800 bucks into the project and just today found out that my engine wont run after putting in a reman crank, oversize piston& bored cyl, crank bearings, full gasket and seal kit, LOTS of expensive hardware, helicoils, new CDI box, and hours and hours of work.

if i could go back to july i would have just saved up and bought a running bike instead of what i thought would be the cheaper route, of fixing up an old bike. now after $800 i dont know if the bike will ever run. if i parted it out, i wouldnt get back near as much as what i put into it.

also its been very hard to find parts for my '92. and its only going to get harder. i cannot get certain parts like crankshafts and water hoses.

its a hard decision to either run away while you can, or dump hundreds of dollars into it and hope that it'll run.

EDIT: did some searching for a crankshaft and couldnt find any.

you can still get a wiseco rod and have a machinist remanufacture the old crankshaft. this is what i did, but someone i knew did it for me. there are places you can send your old crank and they'll do it.

you need a press to seperate the crank halves, press in the new pin, and balance each half almost perfectly. it was a lot of work. this is assuming the rest of the crankshaft is still good.

heres a link to the wiseco rod, only place i could find it is ebay.
http://www.ebay.com/itm/31047307553...ries&cmd=ViewItem&hash=item4849a32b4f&vxp=mtr

if you decide to rebuild this bike i strongly recommend buying a manual. the torque specs are very important on these, and itll show you how to do everything right.

yeah i keep looking back to your bike and seeing all the money and hours that youve put into it. But i think what im going to end up doing is play it by the ear. What i mean by this is that im going to go as far as i can with what i have as if its 2 seperate projects, the physical bike is 1, and the engine is another. So far all ive been working on is the physical bike and today i was able to mount up the front fender and shrouds. What im gonna end up doing is getting the bike portion semi complete like mount the rear fender and then get a good look at everything so that way ive already put it together once and i have a less chance of messing it up or scratching my head with guess work. I say this because after its complete im going to take it apart again, clean up and paint all parts, and then put it back together. This way at least the bike portion is "Ready". Then if worst comes to worst and i cant get the engine running i can sell it as a project and itll look half decent. Heres some pics of what the bike is like now and the first pic is from before but i never got around to posting it...

 

[j.concepcion54321]

Ok so I was checking.craigslist earlier today and I found someone sellng a go kart project with a complete 2009 honda 250cc 4 stroke engine for 250 dollars the whole project. Im thinking about buying it and then putting that engine onto my bike. What do you guys think. Its a 6 speed.

 

[Bluethunder3320]

i think it would be very hard to get a 250 to fit into a 125 frame. who knows though because ive never done it... one thing i know for sure is it wont be a bolt-in thing.. youre going to have to chop it up somewhat

saw a youtube video of a cr500 engine in a cr85 so its possible

 

[j.concepcion54321]

Yeah I figured itd be possible, but after some thought I realized that its not the route for me.

On another note I got some work done on the engine. I played around with all the parts for a while and I now know where everything goes!! It took me agood few hours but hey im happy. Lol.

Also confirmed that the bottom end is indeed seized, but nothing is blown. I think the previous owner went and got tje cases split but never took them apart. So what I did was spray abput half a can of liquid wrench into the bottom end, and then I put the cylinder on and sprayed some more oil down there. I also checked the crank bearing visible from the ledt side and it looks perfect so idt that it will be a problem. After about an hour I tried to turn it over amd it jiggled back and forth a little. PROGRRSS!!

Also got some work done on the clutch. Take a look at the pics and youll see why iy only brought 3 springs...

http://i1205.photobucket.com/albums...TM 125 MX/IMG_20130131_121959_zpse48d9f4d.jpg
http://i1205.photobucket.com/albums...TM 125 MX/IMG_20130131_122007_zpsc09b1593.jpg
http://i1205.photobucket.com/albums...TM 125 MX/IMG_20130131_121952_zps390e6af8.jpg

@Kaptainkrunch..... i think im gonna need that clutch. lol. Would you be able to get me some pics, measurements, and a gear count on the basket so that i can check with mine to see if itll fit? Im also mising the ignition coil, which has what goes to the sparkplug (the boot). Do you have that as well? i remember you saying you had some electrical components.

ALSO!!!! Let me know if the photos are too big, if so then ill resize.

 

[j.concepcion54321]

Anyone have any ideas for cleaning the piston and the crank? to get rid of the rust and crap all over it? I was just thinking angle grinder with a wire wheel attachment and some wd 40. But now im starting to think that that option might leave scratches on it. So im starting to consider engine block cleaner and a rag. lol Which option is best?

 

[j.concepcion54321]

Update 1

First thing i did was bring in the seat. I used duck tape to tape up the exposed areas, and then i came back with some athletic tape. It has a sort of felt, fabric like feel to it and it sticks good so it conformed well to this application. After i was about halfway done i ran out of tape though

 

[j.concepcion54321]

Update 2

I GOT THE ENGINE UN SEIZED AND IT HAS COMPRESSION!!!!!!!!!!!!!!!

Yup you guys heard right, all those days of spraying the bottom end, and down the cylinder with wd 40 and liquid wrench payed off.

I put the cylinder on, and then told a friend of mine who had a rubber mallet to come over so we could try to get the bottom end unseized.

(Sorry no pics of this process i know i know)
Then we went ahead and banged at the piston for a little while, and around the bottom of the case (with the rubber mallet of course) to try to get things going a little and loosen it up. Then i grabbed a huge adjustable wrench and secured it to the flywheel nut, and we grabbed a set of locking pliers and secured it to the other end of the crank shaft. Finally we both tried applying pressure and to try to crank it over. It took us a few tries but between the two of us we were able to break free and after that it was turning over very smoothly. The piston and the cylinder have almost no clearance and it all fits very nicely

After it was unseized i started working to put it back together....

Making gaskets out of cereal box and heavy grease. lolololololol

Came out pretty good though if i do say so myself.

 

[j.concepcion54321]

Our workstation, my messy basement... The shed was just tooo cold!!!

Final Product Up until now... LAST PIC


All in all im pleased with this update. I was able to resolve the original reason it was taken apart, and get the engine pretty squared away. I also hooked up the wiring. The engine now kicks over easily with decent compression

TO DO:
-New plug and test for spark
-Finish bolting the motor together(alot of the side covers were just placed where they go, not actually tightened down)
-Fabricate intake manifold
-Purchase Exhaust
-Clean carb
-Try to start engine
-Take apart rolling chassis
-Power wash and wire wheel to remove gunk
- Paint frame
-paint body plastics
-Install engine
-Mount swingarm
-Put back together
-Rebuild brakes
-Finish seat
-TEST RIDE


....... Id say im getting there.