2 stroke fun for 200 bucks

[hardwaregrrl]

Originally Posted by HapHazard

I'd suggest checking the head to make sure it isn't warped. The shade tree method is to lay it gasket side down on a glass plate (or even against a window) and make sure it's absolutely flat. Small differences can be cleaned up by putting emery cloth between the glass and head and moving the head over the emery in a circular motion. The shop you're having your cylinder work done in could probably check it out on their flat plate.

Also, I'd vote for changing those crankshaft seals now. It'll never be easier or cheaper!

Neat bike! Best of luck!

Aw, shit. So many things to think about. I just ran down and checked it on a piece of marble. Looks very flat to me. I'm a bit nervous to split the cases, and I'm low on dough...so trying to be economical. This thing still needs a bit of money thrown at it.

Hey Richard, the bike and I will both be very un-pc. That's how I like to roll...

[stainlesscycle]

Originally Posted by hardwaregrrl

. I'm a bit nervous to split the cases, and I'm low on dough...so trying to be economical. This thing still needs a bit of money thrown at it.

well once you split the cases you're gonna have at least $100 into seals, bearings and gaskets. there's no reason to split cases and not replace everything. once you're in there, you'd regret not freshening everything up. you could go without splitting them now, wait till it blows up (could be soon, or could be never...) and spend the money then.....

[Stagehand]

Originally Posted by bgoodsoil

I was amazed when Len told me you had the engine out already. Heck yeah! You just earned your Detroit street cred

Anybody know how much work is it to separate the case or what's involved? Does it separate horizontally? I don't have the bike in front of me so I can't check.

I saw someone comment on the thumper forum saying that the left side crank bearing is oiled by the 2-stroke tank somehow? They said that's why you can't run pre-mix in this engine. Anybody know anything about that? Again, it was a random comment on the internet and doesn't make a lot of sense but I thought I'd ask.

Presumably then the bike is oil injected, so theres a seperate tank for each: gas and 2smokeoil, and the thing mixes iteself, while simultaneously drawing oil off the 2msokeoil tank to feed a part of the crank. Normally the whole crank would theoretically be served by the oil in the pre-mix. Here its a partial.
It would probably be going to far to say that this is somehow related to the fact that one crank seal can be gotten to without splitting cases, and the other is different. IMTUAIG
(I'm making this up as I go)

[WVhillbilly]

One of my buddies in high school had a bike just like this. Fun bike, wish I could find one that nice now.

[tbirdsp]

Yeah, I've also heard the Suzuki oil injection system ("CCI") used the pump to lube the main bearings - not good to disable it.

[MightyChosen1]

Originally Posted by One Less Harley

good looking little bike, rings,oversize piston, bore. Have you actually priced pistons lately????? I bought a Wiesco for a MT250, prices are frigin' ridiculous.

I was pretty shocked when I ordered a piston kit for my Dt-175 last week, $147 bucks plus $50 to have it bored. Last one I did quite a few years ago was around $125 including the boring.


Nice bike Hardwaregrrl. I paid double that for my DT and thought it was a decent deal. I look forward to seeing it finished.

By the way my cylinder looked just like yours inside , I was told it wasnt from wear but from a crappy bore job the previous time.

[gvthnks]

don't disable the oil injection system. It'll start and run fine for a few minutes and then the mains will die. as someone above stated, that generation suzuki used the premix injected onto the mains to lube them.

I would clean and inspect each of the hoses that run to and from that oil pump. if any are dry rotted or pinched or cracked they'll leak or cause issues. There may be a oil filter inline somewhere too and that needs to be clean so it doesn't restrict oil flow. By all means get all the old oil out of the oil tank and flush it to ensure it's clean. Any dirt or grime in there will be injected into the motor. I've never seen an oil pump fail if it was run in clean oil. They fail when dirt is allowed into the system or they're run dry. There's also an adjustment that allows the oil pump to be calibrated to the throttle opening. don't remember how it works on a suzi, but your service manual will probably detail it.

If it was me, and it's not, I would most certainly change the crank seals. They're cheap, and after 30 years theyre either not sealing well or they won't seal well under the new pressures that the new piston and rings and cylinder will create. If the magneto side goes it'll suck air, run lean, and you can burn a piston in a hurry. If it's on the wet side, it'll suck oil and foul plugs. Seals will cost you 25-40 bucks for both and will ensure its done right.

I had a TS 185 when I was about 11. To me back then it was a monster of a bike and I could start it but couldn't touch the ground. Was ugly as all get outs, but screamed. Sold it to a friend who was taller than I. I think I weighed about 85 lbs at the time.

[mikenj]

Looks real clean! Did ya get a title?

[baldwithglasses]

Git that durn bahk t' run, Gurrrl!

[PFFOG]

Originally Posted by gvthnks

don't disable the oil injection system. It'll start and run fine for a few minutes and then the mains will die. as someone above stated, that generation suzuki used the premix injected onto the mains to lube them.

I would clean and inspect each of the hoses that run to and from that oil pump. if any are dry rotted or pinched or cracked they'll leak or cause issues. There may be a oil filter inline somewhere too and that needs to be clean so it doesn't restrict oil flow. By all means get all the old oil out of the oil tank and flush it to ensure it's clean. Any dirt or grime in there will be injected into the motor. I've never seen an oil pump fail if it was run in clean oil. They fail when dirt is allowed into the system or they're run dry. There's also an adjustment that allows the oil pump to be calibrated to the throttle opening. don't remember how it works on a suzi, but your service manual will probably detail it.

If it was me, and it's not, I would most certainly change the crank seals. They're cheap, and after 30 years theyre either not sealing well or they won't seal well under the new pressures that the new piston and rings and cylinder will create. If the magneto side goes it'll suck air, run lean, and you can burn a piston in a hurry. If it's on the wet side, it'll suck oil and foul plugs. Seals will cost you 25-40 bucks for both and will ensure its done right.

.........

Good advice here, you will destroy the LH main if you try running premix without the oil pump.

Yes looks like it was lean, could be air leak, or more likely partially plugged jets.

You can bleed the oil pump by loosening the phillips head "banjo" screw on the face of the pump, (this bleeds the tank to the pump), then once it is running just hold the lever on the pump to full open and you should see the oil pulse through the line. To calibrate it there should be a plug in the side of the carb slide body, you remove it and turn the throttle until you see a dimple in the slide through the port, at that point there should be a line stamped in the oil pump arm that lines up with one cast in the pump body.

And what he said about the seals,if they leak. I would only do the mag side though, the clutch side requires splitting the cases and pulling the main bearing. If it sucks oil after you get it running then you will have to split and replace.

Some of the later Suzuki 2 strokes had the nikasil (SP?) coating on an aluminum cylinder, if it does just hone it, if it is a iron sleeve, then it can be bored. The one pic looks like it is sleeved.

[PFFOG]

Originally Posted by bgoodsoil

...........
I saw someone comment on the thumper forum saying that the left side crank bearing is oiled by the 2-stroke tank somehow? They said that's why you can't run pre-mix in this engine. Anybody know anything about that? Again, it was a random comment on the internet and doesn't make a lot of sense but I thought I'd ask.

What Suzuki did with the CCI injection was to inject oil from the pump directly into the main bearings, rather than relying on a "watered down" mixture. As the oil exited the mains it was collected by a "slinger plate" that captured the oil through centrifugal force and was feed into the center of the crank pin, to again provide concentrated oil to the lower needle bearing.

Because of this design the openings in the rod are small, and the main is shielded from the fuel/air mix, thus both will be starved for oil if you disconnect the pump.

[Suzuki Phil]

Originally Posted by Furious D

I was pretty shocked when I ordered a piston kit for my Dt-175 last week, $147 bucks plus $50 to have it bored. Last one I did quite a few years ago was around $125 including the boring.


Nice bike Hardwaregrrl. I paid double that for my DT and thought it was a decent deal. I look forward to seeing it finished.

By the way my cylinder looked just like yours inside , I was told it wasnt from wear but from a crappy bore job the previous time.

Did you look on ebay? I ordered a .5mm over piston with rings and a rod kit off ebay for a total of $70.00, all new parts. Coming from Singapore so I have to wait a few weeks. My bike is a 78 Dt125

SP

[hardwaregrrl]

Hey all. Well not much to report today. Cleaned the holy hell out of the engine and removed the oil pump cleaned it and checked and flushed the lines. I had to bleed the pump on my RT 360, and the pump on this one looks very similar, but much harder to get to. I'm going to take my chances on the bottom end and just run what I've got.

I am having a problem with the forks. I've replaced many a fork seals on the ST, and it was easy. But I have to remove the stanchion and have so far been unable to. Used and air wrench but the damper is still spinning. Reassembled the forks, but that didn't help. I still do not have the manual, and stuff online is not specific to this bike. Anybody familiar with it? Or have any advice ?

[bluebye]

Originally Posted by hardwaregrrl

Oh geez....



I'd say it's toast! Yeah, the piston is really scored, but I'm not sure what to do about the jug?



There is only a couple of places you can actually feel any of the scoring you see here. But otherwise, it is very smooth. So I don't know if I should just get it honed, or go 1 over?

This concerns me too...



Doesn't look like a rat chewed on it, but, I'm hoping the bottom end is ok?

So, I've located a few cylinder heads that the owners claim to be smooth. If there is just a tad of scoring on the head, does it need to be bored one over, or honed, or plug it and run it?! Obviously I'll be getting piston and rings. What say you oh 2-stroke geniuses. Oh, one more thing, I was only able to find synthetic 2-stroke injector oil. How bad is that? Do I have to run mineral?







Hey Brad, I left my beer hiding jacket at your place. Don't use it as a shop rag!!!!!

Oh, who hones/bores cylinder heads out in Atlanta?

Ok, a couple of things here. That hard of piston seizure is lack of oil. The piston has seized to the cylinder at one or more times causing the damage. Find out why there was a lack of oil to the top end or it will do it again. It was probaly ran out of oil and someone poured some in the tank after seizure. The system has to be bled now to work correctly. Procedure in S/M. Judging by the size of the chamfer in the top of the bore, it is std. and will need .50mm to clean up. If the cylinder is at MSP (my shit's perfect good guys) and Roger Baby is still there, talk to him about all this, he knows two strokes as well as anyone there is. The piston crown shows detonation, is the air filter intact and sealing well? Filter, box, and boots. Very important. Doesn't look like timing (advanced) to me, as the points wear and retard the timing. Air leak from somewhere is the cause, above mentioned parts or the mag seal on the crank. If you can come up with a flywheel puller and correctly remove the flywheel from the crank, you may see some tracks of mung and drool from the crank seal. You do not have to split the cases to replace this one, but if it leaking, it will kill your new top end. Beware of the high or erratic idle you cannot correct, with the card and top end and timing correct,as this is the sign of an air leak. Usual carb jets cleanliness,cap sealing apply. At these miles on the bike, the exhaust has issues to be addressed after the above is all correct. Two stokes are simple, but EVERYTHING has to simply work. You will love it. Chris.

[bluebye]

Originally Posted by hardwaregrrl

Hey all. Well not much to report today. Cleaned the holy hell out of the engine and removed the oil pump cleaned it and checked and flushed the lines. I had to bleed the pump on my RT 360, and the pump on this one looks very similar, but much harder to get to. I'm going to take my chances on the bottom end and just run what I've got.

I am having a problem with the forks. I've replaced many a fork seals on the ST, and it was easy. But I have to remove the stanchion and have so far been unable to. Used and air wrench but the damper is still spinning. Reassembled the forks, but that didn't help. I still do not have the manual, and stuff online is not specific to this bike. Anybody familiar with it? Or have any advice ?

So, have you got the fork caps installed and tightened down before you use the air wrench to remove the dampner bolt? Hopefully, because the is the easy way to do it. And you may have to use big twist, like a 1/2 air wrench, with the caps screwed all the way down for resistance.