1979 Suzuki TS250. How hard could it be?

I bought a 1979 TS250 from a buddy's dad.  It had sat in his garage for 10-15 years not running.  Price was good, so I figured I could use it to learn my way around 2-strokes.

Compression was really bad, like move the kick-starter with your hand bad.  I was expecting to see a big hole in the piston top, but when I pulled the head it looked ok.  The piston could be moved around within the bore, so something was definitely wrong, but the portion of the bore that I could see looked good.  At this point, I was thinking I got really lucky and just needed a $30 set of piston rings.

Well, my luck wasn't so great.  I pulled the cylinder, and the piston skirt had shattered.  I haven't figured out what caused it yet.  The bottom portion of the bore has some scratches in it that will definitely need to be bored at least one size up.  Machine shop will have to determine that for me, so I won't order a new piston until I talk to them.  I need to measure lateral play at the rod end.  I can tell it's moving, but haven't quantified it yet.  The real bummer is that all those piston pieces had to go somewhere, so now I'm pulling the whole engine apart.  I knew all along that I would have to do this eventually to replace the crankshaft seals, but I was hoping I could get away with some top-end work and then running the engine for the rest of the season and do a full tear down over the winter.

Other things that have to happen as time allows are a fork rebuild, throttle cable, new brake and clutch levers (mismatched and ugly), tail light lens, blinkers, mirrors, battery.  Realistically, this will never be a full on restoration.  I just want to get it road legal, reliable, and safe at this point.  In Missouri, you are not required to have blinkers or mirrors on a motorcycle, so I may hold off on those for a while.  The only things I need to make it rideable are the engine/carb rebuild, fork rebuild, and throttle cable.

Advice, chastisement, sympathy, disdain, etc. will all be accepted.  Last night I was considering parting the bike out and hunting for a different one, but this morning I decided to roll with it and make this work.  I'm actually a little excited to learn some stuff and do some things for the first time.

Cool bike!  Glad to see you waste no time diving in. 

I would not ride on the street without mirrors. Blinkers are good, too. With bikes on the street, visibility is everything. You need to see and be seen. 

Put mirrors (and I highly recommend also adding the mini blind spot mirrors to them) on it so you can see more of what’s around and behind you!

Blinkers and mirrors will happen at some point.  I used a bicycle as my primary transportation for a few years, and try to ride as though everyone in a car is trying to kill me and every pedestrian is trying to kill themselves.  Until I can trust it, this bike won't go much farther than a couple miles from home.  Population in my town is 239, so I'm not in a big hurry to spend money on things that won't make it go, stop, or turn.

In other news, parts for this thing are ridiculously hard to find.  I need a magneto cover and a sprocket cover.  No luck so far.  There are a couple complete engines, but none that are the right year range, and they are ~$500.  If any of you happen to have a stash of TS250 parts you're willing to sell...

It looks pretty decent - in particular the seat cover is good, and that always seems to be a sign that the bike was well taken care of.  Paul Miller in CT is the go to guy for NOS Suzuki parts.  He has an eBay page at http://www.ebaystores.com/PAUL-MILLER-MOTORCYCLE but not everything is listed there, his contact information is on his website: http://www.millersvintage.com/  For used parts try Sport Wheels in Minnesota, they're probably the largest motorcycle salvage yard in the country: http://www.sportwheel.com/  Otherwise keep an eye on eBay; Suzuki built a ton of TS250s and other 250 variants that used the same basic engine, so the parts should turn up sooner or later.  I actually have some 250 parts, but unfortunately they're off a 1974 RL250 trials bike so the covers are different.

Friggin love 2-smoke bikes on the street. Al Gore can piss up a flag pole.

My first bike was a '74 Yamaha 125 enduro something. Luckily it had compression and was just a carb clean and new points away from running. 

Parts on old stuff can be difficult, just be persistent and patient.

Cool!! Reminiscent of the bike I had in high school. A 73 Suzuki TS185. Like this one, same color but mine didn't have turn signals. Went through me and both my younger sisters, youngest sister wrecked beyond repair. I went through a few sets of mirrors and a tail light, still have elbow and shoulder problems from that one.

I only had about fifteen minutes to work on it this weekend, so I pulled easy odds and ends off the motor.  Shift lever, kick starter, sprocket, and piston.  With the piston off, I could check the end-play in the connecting rod and it was in spec.  I was expecting it to be bad, so that was a nice surprise.  This is how I justify being a pessimist: I was wrong, and it made me happy.

I'm pretty limited on time, so I'm just trying to get small things done every day or so.

I might have found the source of the damage.  I like to leave subassemblies in tact as I take things apart.  It makes things easier to put back together later.  Anyway, I was putting the cylinder in my car in case I have time to run by a machine shop after work.  Since it was in hand, I looked over it again and saw that a piece of the reed valve was MIA.  It's a really light piece, so I'm not positive that it is the cause, but they are steel reeds.  If it broke off and caught the edge of the piston skirt, it could have led to the destruction.  I had ordered a set of fiberglass reeds yesterday morning, so they were on my mind.

Crank seals came in the mail yesterday.  I'm running out of excuses to delay tearing the motor down...

I want to get this written down before I forget about it.

I called a machine shop yesterday to ask if they could bore the cylinder for me.  An older man answered the phone and said I could bring it by and come in the back door because the front is locked.  So I get there and walk around back.  The door has a hand-written sign that says cash or check only.  I walk in, and it's dimly lit, classical music playing, low ceilings, oil stained concrete floors.  Everything is neat and in order, and there are rows of older, manual machines.  The man I talked to on the phone is sitting at a small desk in an adjacent work area, writing something on a notepad.  He immediately picks up our conversation where we left it on the phone - current piston size, what size overbore pistons are available, desired clearance between piston and cylinder wall...  He pulls a new sheet off his notepad, writes down a few dimensions and my phone number, puts the paper in the cylinder, and says he'll call me after they rough bore it to tell me what size piston to order.  When they have the piston in hand, they'll finish bore, hone, and chamfer.  That was that.  He never asked my name, and I never got his.  Now I'm just waiting on a phone call.

I've worked exclusively in bigger, more tech-forward shops, and they just aren't the same.  I really liked the vibe of this place.  I'll have to scrounge up some more broken engines to send his way.

Machine shop called and said the damage cleaned up easily. They told me one size overbore would be plenty, so I ordered a new wiseco piston and rings.

A magneto cover popped up on eBay UK, so I messaged the seller about international shipping. While we were sorting that out somebody else bought it. Bummer. The dude that bought is on another Suzuki 2 stroke specific forum where I asked if anybody had a cover in their parts bin. He messaged me and offered to sell it to me for the price he paid plus shipping. He said he knew I was looking for one, and he was afraid someone else would buy it before I could. How awesome is that? Faith in humanity restored. 

Since parts purchases are coming together, I really need to get to work on the bottom end. The Suzuki service manual calls for a special slide hammer tool to remove the magneto. I'm not buying that, so I channeled my inner GRM and made a tool in about five minutes. 

Steel plate with 3 holes in it and some M6 bolts. I didn't take any pictures of it in use because I didn't think it would work. I also ignored the advice that said don't use an impact driver to remove the bolts holding the cases together. Well I followed that advice, but those babies weren't going anywhere so I used the impact and it worked great. Time wasted, lesson learned. 

Current status.

Bottom end has been stripped, cleaned, and reassembled.  I found the pieces of piston skirt that had broken off.  They had been magically transformed into metallic paste.  I looked through all the gears, and everything looks fine.  Doesn't appear to be any permanent damage.

Piston came in the mail, so I'll drop it off at the machine shop after work today.  They'll probably finish the cylinder in the next couple days.

Throttle cable replaced.

Gas tank has been cleaned out, and it looks great inside now.  Cleaned up the fork and front wheel.  The pictures above don't show it well, but they were nasty.

Current to do list:  Bend the rear brake pedal straight-ish, clean carburetor, finish cleaning oil off of everything, attempt to bring some color back to the fenders, install rebuilt top end.  I'm still a little afraid that I'll get it running for the first time and after a couple seconds, it will start making terrible sounds and die forever.  I don't even have the engine installed, but it's hard to quit thinking about the next step.  I've got an idea for a rear rack with an integrated LED strip tail light and blinkers.  I need to take a deep breath and focus on the tasks at hand.

I got the cylinder back from the machine shop.  They only charged me $50.  Sweet.

Obviously, I couldn't just leave it on the work bench, so I reassembled the motor and put it back in the frame.  Started hooking everything back up, but I still need to clean the carburetor before it gets installed.  Then fill with oil, prime the oil pump, give it a little gas, and kick her over.

I also started trying to breathe new life into these faded fenders.  I don't expect to get them perfect, but if I can get them to look good from 10 feet away, I'll be happy.  My method is to use a razor blade to scrape the oxidized plastic until the good plastic underneath is exposed.  Once that is done, I'll wipe it down with alcohol and hit it with a heat gun.  I'm following this video almost exactly...

https://www.youtube.com/watch?v=KJb5IPOx2l0

Yes I know this thread sucks with no pictures.  I'll remedy that soon.

I've had some luck with using metal polish (like Flitz or Simichrome) to shine up that old flexible plastic Suzuki used for their fenders.

I thought about trying that, but the rear fender on this bike was sooooo bad.  It wasn't just faded.  Under the seat is still bright red, but the parts exposed to sunlight were white.  I thought there wasn't any color left.  I know that sounds dramatic and stupid, but I thought I was going to spend a couple minutes scraping it, give up and start researching ways to paint plastics.  After a few scrapes, I started to see color, so I kept going and it's turning out better than expected.

bigeyedfish said:

After a few scrapes, I started to see color, so I kept going and it's turning out better than expected.

Good deal.  Post pictures of the final product.

Welp, she lives.  Sort of. 

Kick start it, and it fires right up.  This is great news.  Less great news to follow...

The key does nothing.  Kill switch doesn't do anything either.  This is slightly inconvenient in a normal circumstance, like when you want to stop a motor at idle.  It is very inconvenient when that motor wants to run away on you and you can't kill it quickly and easily.  So the motor starts very easily, which gave me a big ole grin for a couple seconds.  Revs started to climb on their own.  Gave it some gas, and it settled down.  That was good enough for me to take a little test ride down the gravel driveway despite the flat rear tire.  Cruising along in first, everything feels pretty good, but I needed to turn around, so clutch in for the sharp turn and the revs take off for the moon...  Uh oh...  Kill switch - no change.  Key off - no change.  Crap, what's plan B?  Clutch still in, kicked it up to second gear, hard on both brakes, let the clutch out, stall the motor, push the bike back to the garage.  I have started it a few times since this for short durations.  It's about a 50/50 chance that it tries to run away.  That inconsistency is confusing to me.

Here is where the questions start.  Any 2 stroke gurus out there, please share your wisdom.  My mind says run away like this is the result of a super lean mixture.  Conventional wisdom says crank seals are the prime suspect, but these are brand new, so I hope that isn't the problem.  Clogged pilot jet?  I started to take the carb apart, but it looked clean and I was feeling antsy, so I just threw it on the bike.  Leaky carb boot?  I think it's sealed well, but the rubber is 40 years old so who knows.  Too much oil in the mix?  Not sure that this could do it, but too much oil means not enough gas which means lean mixture.  I would have expected the oil to cool the cylinder a little and prevent the run away.  Bad exhaust leak at the header?  The exhaust gasket is shot.  I have another on the way, but the old one is in now.  Excessive carbon build up in the exhaust?  I really don't think this can affect it, but I've been wrong a lot in my life.  Carbon starts to burn and affects flow rate through the exhaust, pulling more air.  I don't know about that.

The obvious answer is to pull the carb apart and make it spotless.  Check the boots while reinstalling.  And install the new header gasket.  And burn out the exhaust.  Can anyone rule out any of these possible causes, or suggest others?

Sweet mother.  This thing rips.  The brakes are not good.  And the tires are quite bad.  But it rips.  I am a fool and thought the motor would feel similar to the 250 street bikes (Rebel, TU250, GZ250?) that I've ridden.  I was wrong.  This bike just wants to go all the time - not as though it misinterprets your throttle inputs, but that it convinces you that faster is always better.  I think we'll get along just fine.

To expand on the above, I wish I could have ridden this when it was completely stock - piston and reeds.  I'm sure that the Boyesen dual stage reeds are a factor in throttle response, and I'm a bit curious if the Wiseco piston offers any improvement over stock.

I'm 90% sure the lean condition and the motor's attempted suicide was poor fuel flow from the tank.  I cleaned it some more, and the problem has not resurfaced.  I've got some electrical gremlins to sort out, but after that, I can get it plated and insured and use the country roads by my house to tune it a bit better.

Yea when these come 'on the pipe'  they're a hoot .....embarrassed GPZ900 with my RD400 doing a roll on from 45 mph....good times  

"... but that it convinces you that faster is always better ..."

outstanding choice of words.   

It's pretty wild.  Our driveway from the house to the back of the property is gravel and fairly narrow - I can't drive my truck to the back without brushing against some tree limbs.  I was rolling along back to the house at 15-20 mph, rolled on the throttle, and it picked the front wheel right up.  That was plenty of excitement for one evening.

My wife wanted to join me on a short ride last night.  Obviously, I obliged.  She was giggling the whole time, and wanted to go for a second lap after we got back to the garage.  If this thing burns to the ground tomorrow, I'll still consider it a success.

Two stroke dual sports just exude goodness into the world. Some might not like the smell or the emission but every time I see hear and smell one I grin like a child. When I get to ride one the effect sometimes lasts for an hour.

Happy to see you brought this back to life. Get good riding gear and have lots of fun.

Reminds me of my first go cart. The throttle cable was broken. Once a buddy and I got the engine running we were so excited to drive it that we couldn't wait for a throttle cable. The solution was for him to hang off the back and run the throttle manually while I did the steering. Much success.

Fix the brakes. Party on.

Please be careful yu two.....Do not try a flyin' 'W' EVER!!!!

Before the RD I had 1975 Husqvarna 250cc motox bike....a tank....first motorcycle for me ever.

At an area that was remote at the time (west Houston Tx. 1982ish) I got on that beast and cracked the throttle.

Next thing I knew i was on my back in the dirt and it took off wheeling for at least another 75 feet......I think that display tweaked the front fender   couldn't stop laffin'....

I worked at a Suzuki Dealer for years. We had A LOT of older parts for the dirtbikes. If you ever need engine parts give them a call, they may surprise you

Suzuki of Van Nuys in Los Angeles 818-994-2882

https://suzukiofvannuys.com/