Rebuilt 85 200 es engine No start, tear the pull cord out of your hand.

[McQuade]

Back story: my old trike was smoking bad, so I pulled it apart to rebuild it. Easy as pie. Found it was obviously ran dry by previous owner at some point as the piston was gouged pitted and scuffed. Figured " hey if I'm doing an overhaul I may as well get some oomph" and opted for a wiseco 10.25:1 compression forged piston set. Went well after honing it slightly (it was still perfectly 65mm and no damage strangely) assembled as usual.

Problem: I neglected to realize how hard the sucker is to pull start. It goes half a turn and stops dead and sucks back in. (It will spin perfectly fine without plug or pulled slowly, so no interference issues I checked often) and with the decompression lever used it won't start. I get one good rotation and that's it. So I tried bump starting it. It would roll roll roll "putt" roll roll "putt" as if it's catching but won't keep going. Good fat blue spark. New fuel line, petcock, refinished tank. Took carb apart and did mild cleaning, blew out jets, set mixture sxrew to 2.25 turns out. Same thing. Plug gets wet, beleive me it has compression now, so that leaves timing right? My cam sprocket mark just comes shy on the right of the head mark. It's like not even half a tooth off. Checked multiple times to see if it skipped. Pulse gen is timed at the F line via flywheel. This again circles me back to fuel. I dried it out emptied the carb, heated up the plug while I was smoking with my lighter put a little fuel down the hole and put it back in and when I cranked it I nearly kissed the seat. I'm in the military, and when I say it was like holding a rope attached to a car at highway speed I mean it lol. Please help. Thanks in advance.

[Mackus84]

Seems like youve addressed, what i was going to say. Sounds to me like timing. Maybe go back though and check all that again. I dont think its the carb IMO. Id go back thru the timingjust to be safe. Then reset valve clearance. Piston MUST be at TDC, so align the T on the flywheel, make certain it doesnt come off tdc AT ALL. Then get your cam sprocket on, timing mark perfectly aligned with the mark on head cover. When that is spot on correct, then set the ignition timing. Idk it really seems to me like a timing issue. But i could be wrong

[Mackus84]

If trailprotrailpro ignition timing is on, you can still get a spark, even if trailprotrailpro valve timing is off

[atc007]

Timing is off. T on flywheel, although they will usually run on F also. A lot depends on the chain stretch and degree of timing. They love to roll on past TDC, so watch that. Double check valve overlap and adjustment,,.003-.004 unless it looks like a bigger cam? Work on these or sleds long enough and you will have your arm torn completely out of it's joint. Feels like you lost some fingers also right?! It hurts :) She'll run like a champ,because you've perfected everything else lol.

[McQuade]

I agree with all of this thank you. This poor thing was abused bad when I bought it, I only wanted the engine so I asked if it smoked, started it and no smoke. Got it home.. Checked the oil and not a drop lol. Clever guy... Not so clever me apparently. In any case I tried retarding the spark timing.. It chug chugged"" a little better but no start. I think I'll end up pulling the cam cover back off and re check. I retarded it in hopes of be able to pull it a little easier haha. I'll post a pic tomorrow of the marks but as I can tell it won't perfectly line up because of the tooth lines up with the head but the cam sprocket mark is in between the teeth. I really wouldn't think half a tooth early would do it.
Valves, I DID end up replacing the cam it was worn to the point I can't beleive it ran. Had a good one laying around. Checked rockers after and there was slight play, not too tight, maybe on the loose side even, but I left it like this because I'd prefer compression to noisy engine.

[Mackus84]

Yeah i bought 2 200x's and they hadnt ran in 15 years, and the motor im building was in pieces. I honed the cylinder myself, used the manual to put it all back together, getting the timing chain on the right tooth was a pain for a little bit but once i got it on and follwed the manual exactly, it fired up on the first kick

[McQuade]

Most of my mechanical experience is on heavy diesels and two strokes. But this engine is so simplistic... And still it throws me fer a loop. Here's my observations : the cam line will not quite line up. It's pointing just right or just left if the head mark. Nothing I do changes this. Also with the pulse generator there appears to be near to no change from the F to the T line. Very little difference. The reason I finally rebuilt it was that one day the missus was puttering around and when she stopped so did it, and wouldnt start. So I figured the rings finally were toast. What it ended up being as I disassembled it, was the dowel on the cam fell out lol. But I put a new ish cam in so crisis averted.

[atc007]

They often won't line up perfect. I can see you know what you're doing by your post. At this point,it should run lol.Recheck ,and line up the T. It should run with the timing there :)

[muthey]

on a side note, and I have done this before take the pulse generator and remove it from the spring assembly rotate it 180 degrees and reassemble. Now put it back in and try again, if it came out of the spring assembly and you just put it back any which way you can be 180 degree out on your spark. I fought with a machine because of this for about 4 days till I figured it out.

[Mackus84]

Most of my mechanical experience is on heavy diesels and two strokes. But this engine is so simplistic... And still it throws me fer a loop. Here's my observations : the cam line will not quite line up. It's pointing just right or just left if the head mark. Nothing I do changes this. Also with the pulse generator there appears to be near to no change from the F to the T line. Very little difference. The reason I finally rebuilt it was that one day the missus was puttering around and when she stopped so did it, and wouldnt start. So I figured the rings finally were toast. What it ended up being as I disassembled it, was the dowel on the cam fell out lol. But I put a new ish cam in so crisis averted.

Yes, the marks are really close to each other. Make sure youre lining it up with the little line and circle mark for the T and F and not the actual letter. At least thats how i did mine. Dont forget, after you line up the T and have the cam right, you have to rotate the engine COUNTER clockwise 1 complete revolution, then line it up with the F mark and set the ignition timing. You cant just have it on the T and line up the marks, then move it over to the F and set the generator timing. And you said you had spark so we wont go through that part.

[Mackus84]

Not sure if you have a manual, but here are screenshots from my 200x. Timing the motor is the same on either machine229128229129

[McQuade]

Yes, the marks are really close to each other. Make sure youre lining it up with the little line and circle mark for the T and F and not the actual letter. At least thats how i did mine. Dont forget, after you line up the T and have the cam right, you have to rotate the engine COUNTER clockwise 1 complete revolution, then line it up with the F mark and set the ignition timing. You cant just have it on the T and line up the marks, then move it over to the F and set the generator timing. And you said you had spark so we wont go through that part.

That's actually exactly what I did, set the cam, on T then nudged it over to F. But since then the engines been rotated over and over. No change.

[lennycknaus]

Did you turn the gas on

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[McQuade]

Appreciate the input but yes I did lol. In any case I think I've found the issue. So I checked timing again and again. It all added up. So I literally checked top dead centre via handy screwdriver in the hole and 229134 it was sparking halfway through compression hence the wicked pull back. So my question remains, if my cam sprocket is lining up, what the heck have I done?! Lol

[Mackus84]

That's actually exactly what I did, set the cam, on T then nudged it over to F. But since then the engines been rotated over and over. No change.
I suspect this is where your problem is. If you just nudged it over to the F mark, its trying to fire at the same moment the intake valve is open. The purpose of turning the crankshaft counter clockwise until it comes all the way around and back to the F mark when setting the spark/ignition timing is so that it fires on the NEXT stroke. I think its trying to fire at the same timeits pulling in the fuel from the intake. Start over and do it the way the manual explains it EXACTLY. And i think you will get it to fire. The timing is still off IMO. Im pretty certain this is your problem

[Mackus84]

Also, when you installed the cam, you had the lobes facing down correct?

[McQuade]

Update, after finding actual tdc I moved advance as much as I could counter clockwise and it nearly starts every time. Perhaps the strokes now changed because of the HC piston?

[Mackus84]

Update, after finding actual tdc I moved advance as much as I could counter clockwise and it nearly starts every time. Perhaps the strokes now changed because of the HC piston?

That, i cant answer bud. Im new to breaking these motors open too. Hopefully one of the experts can chime in. Im actually pretty curious to find out what is gonna get it going

[McQuade]

It now fires and essentially runs as long as I'm pull starting it, which is a breeze as it's firing and helping. But as soon as I stop pulling the cord it won't keep going. Plug is dry. Given my results (tdc is NOT the T mark for some reason and my ignition is retarded at maximum. Where have I gone wrong? I never pulled the flywheel or anything I don't even know if it was right to begin with. Should I scribe a new line at tdc and another just before? I'm starting to over think in my excitement so I need to step back.

[Mackus84]

Hmmm. That idk either. Unless you sheered the flywheel key

[atc007]

Check the flywheel key /magnets and stator. Somethings going on somewhere.

[Mackus84]

Did you ever figure this out?

[ps2fixer]

Hmmm. That idk either. Unless you sheered the flywheel key

I was about to post this lol. Sounds a lot like the flywheel is missing the key or is sheered. Don't matter what you do, the T mark on the flywheel should always be TDC as the crank/flywheel isn't modified or from another machine.

[McQuade]

So it's running, and it's running GOOD. I ended up finding true top dead centre, and I was three teeth off. Didn't bother with the markings lol. Thanks guys!

[ps2fixer]

Good luck. Hopefully whatever reason the flywheel is off clocked from the crank won't cause you any issues in the near future.

[350for350]

I think you need to check your cam chain. It could be stretched. I don't recall you mentioning it.