Suzuki DS80, no CDI or points?

[Chronic]

View attachment 8622

that's how mine was cleaned it up and a little sealer and was good as gold

 

[Chronic]

how come theres so much fuel sitting at the carby??

 

[heliboy89]

Chronic I think that was WD40 from when I was spraying it down the throttle cable cap, I think... But it has been running rich, the idle is set on the rich side. Either that or it got in there when I opened the fuel **** with the fuel line disconnected I don't know lol. I ran it again it's not reappearing.

I sanded down the face of that intake pipe and it's pretty smooth, put a gasket between it and the cylinder... Pretty certain it's not leaking.

Can anyone confirm that it is in fact leaning out in those first two videos I posted?

 

[my67xr]

i'm happy that there are no vac leaks.

but i still think there is a problem in the pilot jet
either in the main hole, or in the holes across the side of it.
by any chance do you have a drill bit set like the 10 piece micro drill .3mm - 1mm
the centre hole of the jet can look clear, but still have enough gum dried to the inside of the jet to restrict it enough and cause problems.
eg being too lean down low, the bike doesn't rev crisply like it should.


i think the slide is sitting a little too high, and it would be running mainly on the needle and causing it to be rich.
it is also masking the pilot circuit problem.
can you source a new pilot jet locally ?

 

[heliboy89]

The only place there could be a vac leak is under the fly wheel, can I spray something on it to check for an idle change?

I would be surprised if the pilot jet had anything left in it, with the amount of carb cleaner + compressed air + wire that has gone through it... I can pull it out again and try reaming it out though, I will have a drill bit that will fit in there I think.

I don't think the slide can go any lower, the front of it is sitting in its groove inside the housing - when the idle screw is fully out, the slide is completely choked closed...

Are you saying you think it is running too rich?
I'm not sure about a pilot jet locally, I may get lucky if I hassle one of the workshops that had mikuni carbs lying around but none that would stock new ones, no... Better off ordering online if I'm gonna go that route.

 

[GooseMan]

sometime not even wire will clear the jet, I know you have cleaned and all but it is just that all the symptons point towards the pilot jet. if it were electrical it usually affect the top end, ut not allways so ddon't rule that out. like I said I had to use caustic soda over night once!
Doesn't sound like a vac leak to me either.

 

[my67xr]

hearing your bike rev, it isn't crisp, which is the pilot circuit.
and i think that by raising the slide to get it to idle is masking that pilot problem

to only other place it may be blocked is in the air filter side of the carby, the small port at the bottom centre,
if you shine a torch in there there is a small brass jet with a tiny hole in the middle.



to check the l/h crank seal,
you could smear some grease around the seal on the stator side of the engine
then refit it all back together again and try it.
see if the revs change before and after

 

[GooseMan]

ok well I just watched the video (probably should of done that before) and to me it could actually be electrical otherwise it is a mixture issue. My kdx250 had a head light wire with a break in the wire inside the insulation and when the rpm increased it woud get to a certain rpm and just die, or try to.

 

[heliboy89]

Gooseman - to the first post, I know wire might not always clear it but I have checked it pretty thoroughly, it is a crisp circular hole unlike it would be if it had gum on the walls you know, but I will check again to be sure i'll see if I can get a drill bit in there to ream it out.

To the second post - I think you are right, carb fault, or electrical fault. Did you read the bit about the funny things with the timing light?

Another thing I should mention to everyone reading, I did take it for a ride with a timing light on my lap, shining it at the tank to see if the spark stopped and it did stop flashing while the engine is bogging. But the light also stopped flashing at certain RPMs when the engine was running fine, and it would start flashing again if I let it bog right down into lower RPM (bike not firing). So I deemed the light to be a bit faulty or not designed for high frequency 2-strokes. But I guess it could be a weak and absent spark upsetting it?
That plus that weird thing where the light was flashing at TDC AND BDC... Plus the no continuity between primary coil terminal and earth... Maybe it is the coil...? If it is the coil I'll be parting the bike out, it's not worth spending that kind of money on.

my67xr, the wire in this photo is going straight through that jet, I spotted it and checked it was clear it's a crisp circle.

Is there a way to remove that jet that you're talking about?

I will try covering the LHS crank seal in grease that's a sweat idea.

It's probably worth noting I can get the bike to rev quite nicely in neutral, if I lean out that pilot screw, but once it's set like that it has no power, bogs way too early.

Did we agree it was leaning or richening... (if it's not the coil..)
Josh

 

[heliboy89]

I've removed all the wires that aren't neccesary, it has the 3 wires coming from the stator to that harness, then only 2 wires coming from the other side of the harness, I did away with the lighting wires. One goes straight to ground which as far as I understand - is useless as it goes from ground to ground, the other is the black/red ignition one. I've tried with the kill switch disconnected too so it's not a wiring prob. Coil if anything electrical..

Maybe I'll try replacing the wires from the stator to the ignition coil just to be sure... I really only need the one going up to the coil to be testing right...

That's probably me for tonight anyway lol back at it tomorrow.
Thanks again guys

 

[heliboy89]

Interesting ride I just had - I left the air box off it, went riding with the bare carb intake exposed and it produced the same results but I had it going down the road wide open throttle, bogging and surging away as it does and I was able to reach down and stick my hand partially over the intake pipe, it came to life and just about threw me off the back, so I guess we can say this is definitely a mixture issue and rule out the coil.

Another interesting point, I got it to WOT and screaming nice and high in RPMs, as soon as I removed my hand it bogged down again, still with WOT - so maybe this is a main jet/needle issue and not a pilot jet issue?
But they are both clear I swear... :'( What am I doing wrooong haha

 

[heliboy89]

Restricting air and getting a gain in performance would imply it was running lean, so I've either got a nasty ass leak somewhere, or not enough fuel getting in. I'll put a drill through both jets and do the grease test on the LHS crank seal... Back later with the results

 

[GooseMan]

well this is good news, half way there now, if you can see crisp hole through the jets then they should be fine, if it was running fine when you were younger and nothing has been changed or replaced then you won't need to buy jets either. so having sat there for so long somthing has become gummed up or stuck....but what?

 

[my67xr]

let us know what jets it is running too, pilot and main

 

[zwebx]

Restricting air and getting a gain in performance would imply it was running lean, so I've either got a nasty ass leak somewhere, or not enough fuel getting in. I'll put a drill through both jets and do the grease test on the LHS crank seal... Back later with the results

+1 to that

 

[heliboy89]

Let me do the grease on the LHS crank first, I'm running new wire from the stator coil to the ignition assy, just because I've got the stator off and it is in sore condition. I will get it running without touching carb just to see if grease makes a difference and if it doesn't, we'll know its carb for sure.

I can fill a Windex squirt bottle with petrol and just take that riding - failing that ^^.
Thanks guys back in a bit

 

[heliboy89]

Covering that LHS crank seal did nothing, I don't think that's a very conclusive test anyway it would easily suck the grease through a leak and burn it. But since it held 16 psi for so long I doubt they are the problem... And it looks good, still soft and clean. Do I need to wipe the grease off or can it live there.

I wonder if removing the main jet all together and taking it for a ride like that is worth it lol...
I'll get the jets out tonight and figure out what they are.

 

[heliboy89]

Okaaaaaay I think we're finally getting somewhere!!!

I just did a bunch of stuff to it, and got it running quite differently to how it has been. I can hold the throttle against the stop and it won't rev out - but sounds very different, doesn't die, and is flooding the shed with thick smoke now, as you'd expect because I've left the needle on its richest clip which will be way too rich. Too dark to tune it now but I did take it for a ride holding a torch, same deal, got to second gear, full throttle, no dieing, but it won't wind out. I think If I take that clip back down to where it was, we should be somewhere close... Does one clip position make a noticeable difference?

So first thing I did was clean the jets again with a piece of wire, spent a while on it, I don't know if it improved them or not but I spent a bit longer this time.

Second thing was I noticed a slight discolouration on the needle, about 5-6mm down from the bottom clip groove. Couldn't feel anything on it when I ran my finger over it but I ran a craft knife over it and it caught it, seemed to peel it back to bare rough steel - it's almost like corrosion of some sort? I scraped it all off anyway then put the needle in a drills chucks and ran it at max speed while rubbing wet/dry 1000grit up and down it, until it was back to smooth. I suspect this is what the problem was, maybe it was disrupting the fuel flow past it even though it wasn't particularly extruding? I don't know...

Another thing I hadn't noticed was this passage in the carburettor;

Starts inside the pilot jet shaft then exits here;

I didn't realise there was anything inside the pilot jet shaft but there is a little hole in the side and it runs along that rib in the housing, and appears somewhere in the air screw circuitry, neither ends are exposed so, difficult to clear with wire but I put my fingers over certain passages and made sure I could feel pressure on it when I blasted it with air. Not sure if it was blocked or not, but it's not now...

Incase I run into dissapointment tomorrow haha...
Main jet is 87.5 (or is it 875?)
Pilot jet is 52
The needle has written on it 4L27 (probably why I found the discolouration on it)
Do these look clear to you guys for their size?


What are these things exactly? The little copper looking buttons at the end of passages, any chance they could spring a leak?


Fingers crossed I will get it running properly tomorrow! Will be back to let you know how it goes.

I think I will burn the pipe out anyway, while it's on the shop floor, seems to be squeezing smoke out of any nook and cranny in the baffle joints etc, maybe there is a bit of blockage in there.

How did you get the tank back to such good nick in your rebuild 67xr? I sanded the wheel guards with 80 grit then 150 then 400 then 1000 then 1000 with water and polished them, they came out awesome, but I couldn't get the tank to come back as nice, too much discolouration where the graphics used to be and fuel spills etc...

Might be getting ahead of myself anyway will let you know how tomorrow goes.

 

[heliboy89]

That passage doesn't exit where that arrow is exactly, but about half way between that hole and the copper button on the opposite of the passage, bit careless that I missed it though I suppose...

 

[GooseMan]

She might run again then? Check out the bottom of my ds80 thread to see how I did my fuel tank, it didn't get rid of the sticker marks though. Craig (67xr) did it a similar way.