Trouble with Mr. Duc.

[MTS620]

My ST4s decided to take an unscheduled rest at a co-workers house yesterday morning as we were getting ready to head up to Portland for a meeting. It ran great from my place over to his house. When I went to start it up again, it backfired (front fired, what's the correct term?) through the airbox and cranked but wouldn't start. On subsequent tries it turned over, fired briefly and then died. I checked the bike out today and it cranks fine but it doesn't even fire now. I'm guessing it's either a fuel or spark issue, but I need to get it back to my place before I can start trouble shooting.

I have a small pickup I can use to haul the bike, but I don't have a ramp or trailer. Does anyone have one I can borrow for a few hours this weekend? I'd happy to pay in cash, beer, or computer expertise.

-Mats

[TOM-CAT]

I've got a ramp you could borrow. Its not very long, so if you have a raised or high truck it might be close. I used it on Ford 350 rental vans.

The bad firing sounds like a timing issue. Have you ever adjusted the timing? Kinda sounds like a timing advancer came loose, and moved forward advancing the timing to the point that it fired into the airbox. Then moved to a point where no spark is being fired. :idunno:
:2cents:

[tlrmike99]

Not sure about the Duc... but on the TLR there were issues with the boots from the air box to the injectors. THe big twins would hic-up and pop it off, then they would barely run and foul the plugs??? Worth checking... Not even sure if the st is a twin...LOL....

[MTS620]

I've got a ramp you could borrow. Its not very long, so if you have a raised or high truck it might be close. I used it on Ford 350 rental vans.

The bad firing sounds like a timing issue. Have you ever adjusted the timing? Kinda sounds like a timing advancer came loose, and moved forward advancing the timing to the point that it fired into the airbox. Then moved to a point where no spark is being fired. :idunno:
:2cents: Thanks Tom. :bow: I've got a stock 2 wheel drive Nissan so it's not too high. I bet your ramp will work great. I'll PM you my contact info.

Last August (less than 6K miles ago), I had Bend EuroMoto go through the bike to make sure the maintenance was up to date. I assume they checked timing......

I'm not much of a mechanic so I'm going to start with the simple stuff first. Checking all the fuses, electrical connections, plugs/wires, and the airbox, like Mike Suggested. (BTW, it's a twin :rad:) . Right now, I'm kind of thinking it's an issue with the fuel pump because I'm not hearing it when I turn the key to the ON position. I just filled the tank the evening before, so it could also be bad gas, but I have to drain the tank anyway to get at the fuel filter (and pump, I think).

I have a shop manual and know how to read :victory-s but, even with that, it won't take me too long to get to the limit of my competence. :o At least with the weather like this, I won't be to bummed if it takes a few weeks to figure it out. If it's not fixed by then, I'll have to take it in to visit Clint for a little while.

[dansrc51]

If Tom's ramp doesn't work, PM me and you can borrow mine. it's an 8 footer.

[MTS620]

If Tom's ramp doesn't work, PM me and you can borrow mine. it's an 8 footer.Thanks Dan!

[superhawk ben]

My hawk would do that sometimes and foul out the rear plug almost every time and if I could get it runing I had to keep on the gas or it would die.

[Redline]

Pull the timing belt covers. I bet it striped a belt.:sad:

[rickster]

My 888 broke a cam belt @ 12,120 miles during a track day at Buttonwillow. The recommended replacement interval was 12,000 mi. Go figure! Here's hoping that's not the problem wih yours. Mine bent the front cyl. intake valves slightly.

[MTS620]

that's pretty much my worst fear. I finally got the bike home today and need to drain the tank so I can pull the covers and check the belts.

Tom, your ramp worked great. Thank you. I can drop it by anytime. Just let me know where.

-Mats

[ZRX_PAUL]

Mats, contact Jon T about it if you have not already. He knows how to work on Ducs ( He has 2 and 1 is a ST4) and would be more reasonably priced than a dealer.

[TOM-CAT]

...Tom, your ramp worked great..Glad to hear, Mats. :yes: No real rush on getting it back. If you think you might need to move the bike again, to a shop or buddy's house, in the next month or so, feel free to hang on to it for the time being. Otherwise, I can just stop by one of these days and take it off your hands.

Good luck getting the engine sorted out. :thumbup:

[MTS620]

Mats, contact Jon T about it if you have not already. He knows how to work on Ducs ( He has 2 and 1 is a ST4) and would be more reasonably priced than a dealer.Thanks, that's a great idea. If I can't work through it this weekend, I'm going to need some help from somebody that knows how to work on these things.

-Mats

[MTS620]

The update is that it has spark and the timing belts are good. I've checked all the electrical connections and fuses and they all seem fine. Next is checking the fuel delivery....

At least it's not my worst fear. :yes:

[superhawk ben]

The update is that it has spark and the timing belts are good. I've checked all the electrical connections and fuses and they all seem fine. Next is checking the fuel delivery....

At least it's not my worst fear. :yes::thumbup: Good news hope it's some thing little.:thumbup:

[MTS620]

Well the pump seems to work. I couldn't hear it before because the tank was full. :redface: I changed the fuel filter and checked the hoses and wires to and from the pump assembly inside the tank. Everything is fine there so I'm going to try to fire it up this afternoon, but the battery is dead as a door nail. I know I can jump from another bike, but I'll have to drain the tank so I can lift it to get to the battery. Is it safe to jump start it from a car as long as the car isn't running? :kfc:

[roadrunner]

Is it safe to jump start it from a car as long as the car isn't running? :kfc:

every jump ive ever done was with the car(truck actually) running. ive done it twice to the race bike which is a stock street bike anyways and at least sevral times to my daily riding bike.. the only problem ive ever had was the alligator clamps for the jumpers dont fit the bike so well.. i got a bike set of jumpers and the clamps were better but the juice was far lower it seemed. anyhow.. dont leave the things attached any longer than it takes to get the bike started... im remembering another bike ive jumped from a car as well noe that im into this post... piece of cake... and good for you to do this...as it should be.. kepp the riff raff to a dull roar.. :rad:

[MTS620]

every jump ive ever done was with the car(truck actually) running. Thanks. If I ever need to do it that way, I won't be scared. :yes:

I finally bought a battery tender. Cycle Gear has the juniors on sale for only $29.99. I put it on the charger this morning so hopefully I'll be able to fire it up tonight. :rad:

If it doesn't start, I'm taking it to visit Jon for a while.

[roadrunner]

Thanks. If I ever need to do it that way, I won't be scared. :yes:.


the first time i did it i was thinking that maybe my buddy was being an ass and trying to trick me. it was something to hook them up, i was waiting for the zap. i still dont like doing it but will when i need to. easy... yay for the tender. i use mine mostly for recovery and the occasional harley ahha

[MTS620]

So I finally gave up and brought the ST4s in to see Jon. Good call Paul. He found the problem right away, changed my steering head bearings, and I even got the 24,000 mile service done. His rates are very reasonable. I still need to change the brake/clutch fluid and oil, but even taking that into account, I saved some serious $$ compared to what it would have cost at a dealer. Thanks Jon!

[tlrmike99]

OK, after two pages of posts, WHAT THE HELL WAS IT!!!!:nutkick
You gotta tell us.....it's the ESB Mystery!!!!

[MTS620]

OK, after two pages of posts, WHAT THE HELL WAS IT!!!!:nutkick
You gotta tell us.....it's the ESB Mystery!!!!

I can't tell you that. I'm far too embarrassed.:o:o

well..... maybe....




OK, I guess I can tell ya......

The tubes that connect the airbox to the throttle bodies were loose and it was sucking in to much air to achieve combustion. *I Swear* I looked at that. It's just as well that I took it in, the bearings replacement was much needed and I got the valves checked and belts changed too. :smilewink

[tlrmike99]

Not sure about the Duc... but on the TLR there were issues with the boots from the air box to the injectors. THe big twins would hic-up and pop it off, then they would barely run and foul the plugs??? Worth checking... Not even sure if the st is a twin...LOL....


Ooooooo.... Do I win a prize...LOL. :bounce:

Glad you got it fixed, and the other stuff done... just in time for riding season...:ride:

[MTS620]

Ooooooo.... Do I win a prize...LOL. :bounce:


Sure.:clapping:

[TOM-CAT]

Ooooooo.... Do I win a prize...LOL. :bounce:

Glad you got it fixed, and the other stuff done... just in time for riding season...:ride:

Way to go Mike! Nailed it right on the head. :clapping:

[tlrmike99]

TLR's do this often. I actually took the tank off and spun the clamps so I can reach them with a ling screwdriver without taking anything apart. I tighten them every oil change....