Wrenching help in SF?

[connman]

I initially posted a thread about this over on ducatimonster.org, but there seems to be a much more active community here - I'm hoping someone can help.

As I discovered last night, it's sort of hard to get anywhere in San Francisco without being able to climb hills.

This is my first bike - a 2000 M750 Dark with 2800 miles on the clock that I bought private party a couple months ago. I believe the most recent tune-up was sometime last fall, and I'm pretty sure most of its time since then was spent sitting in a garage. Unfortunately, that hasn't changed much since I hadn't had time to ride it until this weekend.

Everything was going well until I started to go up a pretty steep hill - had to get on the throttle a bit and it immediately bogged down and started struggling in a big way. I was basically going about 25mph in 1st and, regardless of throttle input, the bike wouldn't go any faster. The exhaust tone got lower and sounded like it the cylinders were firing much slower. This morning I checked, and it does the same on flat ground - give it more than ~1/3 of the throttle and it falls on its face.

I can only assume it was like this when I bought it and I just hadn't noticed, as this is the first time I've had a chance to take it for more than a spin around the block, and I've been easy on the throttle while I learn to ride.

So, where to start? Carbureted engines are new to me, but I've been reading up and it seems like one of the jets could be gunked up? I'm planning on picking up a Haynes manual tomorrow, and possibly new plugs and some sea foam/carb cleaner. Should I replace the fuel filter? Drain the gas tank?

This is probably a long shot, but if any Ducati riders in SF are feeling generous and would like to help a bike newbie out with the troubleshooting sometime this week, that would be amazing.

Since that post, I've been reading about everything I've been able to get my hands on about our bikes and carburetors in general - I've got a Haynes manual on order that should come in sometime this week. I've also bought new plugs, some carb cleaner, sea foam and a new fuel filter which actually appears to be a used fuel filter (didn't notice this until I got back home ).

As best as I can tell, this sounds like I'm a great candidate for the owner of a pair of carbs with varnished-over jets. To add insult to injury, when I was test-riding it on Sunday to get a better idea of what was wrong, it bogged as I made a slow uphill right-hand turn, and I (gently) dropped it, breaking off the tip of my brake lever. At this point, I'm just really bummed about my new purchase and nervous about trying to tear down the carbs by myself

If anyone in the peninsula would be willing to help out - even if it's just to narrow down the cause - I would be really grateful.

[DanTheMan]

I was thinking carbs before i finished reading the full post. Any time the gas sits too long they get dirty. And once you open it up youll see it doesn't take much to clog. Carbs are one of those mysterious mechanical things that seem like a big black hole of how it works, until you get into them. To tear down and clean is not too difficult. Just remember where everything goes and put it back the way you found it. The manual should be able to guide you through it. May need a tuning when your done, you'd have to feel it out once its running.

Clean carbs
Change spark plugs
Fuel filter
Oil if its been sitting

[Popeye the Sailor]

In other news, unless you have some documentation showing it's been done recently, you're belts are *seriously* overdue.


As in, do not start the bike again overdue.

[Spidey]

I initially posted a thread about this over on ducatimonster.org, but there seems to be a much more active community here - I'm hoping someone can help.

If anyone in the peninsula would be willing to help out - even if it's just to narrow down the cause - I would be really grateful.

Yeah, we were all over at the DML.  Then we left when it was bought out by corporate overlords.  It's a graveyard there now.  We live here.   

Like DanTheMan suggested, start with the simple stuff -- oil, fuel filter, plugs, new gas, etc.  You probably just have old, bad gas junking up the work, but it also might require a carb clean.  Belts are a really, really good idea too. 

You in the penninsula or in SF? 

[connman]

Good to know about the forums switch - guess that explains why I've gotten one response over there in three days, and three responses here in less than one.

As for the belts, the PO said it was in for a tune-up at Desmoto last year. I'll double-check the belts to make sure they look newish. Is there an easy way to drain the tank, or do I need to siphon?

Spidey - I'm in a tiny apartment in the mission, sorta near Dolores park. Not sure where I'm going to be doing this work either, now that I think about it.

[DanTheMan]

Is there an easy way to drain the tank, or do I need to siphon?

there should be a fuel line out of the petcock to the carb that you can unplug and drain.

[Spidey]

there should be a fuel line out of the petcock to the carb that you can unplug and drain.

Carb set-ups are so much easier.

If you know the PO's name, see if you can call Desmoto and ask them what they did.  They keep invoices on the computer.  I'd do that first. 

I don't know what kind of a rush you're in.  I'm slammed this weekend and prolly the next, but have time after that.  I'm in Noe and have a big-ass garage and prolly all the tools you need. Desmoquattro is pretty close to you too.  Sounds like someone should arrange for a tech day and you'll have a buncha hands to help.  Carbs are carbs -- scary to complate, not that hard once you've done 'em.  Even if you go at it alone, if you have a Haynes manual and the DMF, anything can be accomplished.   

BTW, did you find the parts diagram at ducati.com?  Really helpful.  They have it for your year and model. 

[enzo]

Wait, I must have missed something, why are you draining the tank?  If it's for the fuel filter, look on the right side of the bike, just under the seat.  You'll find the filter there.  Otherwise, I'd hesitate before draining the tank.  There might be crap floating around that will clog up your fuel lines.  I would get the bike running first, just so you don't add another variable to the problem.  Once it's running, drain the tank.  If the bike fouls up at that point, you'll know what happened.  If you think bad fuel is your problem, just be aware when draining.

Hopefully it's just a matter of a tune up.  I've had lots of problems with my carbs.  It's a dark art getting the darned things to work right.  In my experience, problems had stupid easy solutions that only revealed themselves after I tore the bike apart a few times...

A few things to check, based on problems I've had: 

1.  Turn your idle screws all the way clockwise, then back them out four turns.  That *should* help/confirm some low speed performance.
2.  Make sure your breather hoses all go to the correct neutral air chambers.  I had problems at high speed that turned out to be a turbulence with breather hoses.  This was an easy solution that didn't come up until I had spent weeks and weeks agonizing. 
3.  Make sure there are rubber plugs on the holes at the float bowls (front of the bike).  They should be about 1/2" diameter.  The plugs were meant for a fuel cooling (or was it heating?) system that Ducati sold for the older carbed bikes.  If the plugs aren't there, then cold air will affect carburation, causing the bike to bog.
4.  Make sure the carbs are seated PERFECTLY on the engine and the clamps are screwed down.  This is trickier than it sounds, and even the smallest leak will mess things up.  Don't do what I do and push one end down, then the other.  You'll be seesawing the carbs for a whole afternoon trying to get it right.  Duh.  Loosen both clamps, give it a good even push, confirm it's seated, then clamp evenly, making sure the clamps don't shift when tightening.
5.  You should balance your carbs, or at least check the balance.  I think some folks know how, but it's an easy task for Desmoto.
6.  Do a little dance before starting the bike.

[connman]

Wait, I must have missed something, why are you draining the tank? 

It seems like the bike has probably been sitting around a lot longer than the PO said it had - I'm assuming the gas is probably bad and at least contributing to my problems. Would siphoning it rather than draining it prevent it from clogging up the lines? I can't seem to find a good diagram of the line DanTheMan was talking about, but I assume it's flowing through a lot of stuff before it gets to that point?

I don't know what kind of a rush you're in.  I'm slammed this weekend and prolly the next, but have time after that.  I'm in Noe and have a big-ass garage and prolly all the tools you need. Desmoquattro is pretty close to you too.  Sounds like someone should arrange for a tech day and you'll have a buncha hands to help.  Carbs are carbs -- scary to complate, not that hard once you've done 'em.  Even if you go at it alone, if you have a Haynes manual and the DMF, anything can be accomplished.   

BTW, did you find the parts diagram at ducati.com?  Really helpful.  They have it for your year and model. 

I'm not in any real hurry, other than I'd just like to get back up and going. But I'd much rather wait and do it right than tear into it and make a mess of things. I was thinking of just taking care of the basic stuff this weekend with the plugs and fuel to see if it makes a difference. If that doesn't do the trick, it would be great if we could take a look at the carbs the next weekend or the one after - I'll bring the beer.

Hadn't seen the parts doc before, but that'll definitely come in handy.

[enzo]

IMO, either way the crud will float to the bottom as the fuel level goes down.  It might not be a problem, just something to think about.  I think the easiest way to do it would be:

1.  Close the petcock.  Look for a silver grooved valve where the fuel line meets the tank, turn all the way off.
2.  Disconnect the fuel line from the back side of the fuel filter.  Some fuel will spill, so be ready with a bucket.
3.  Put the line in your bucket, then open the petcock to drain the tank.

Siphoning works to a point, but fuel tastes bad, and it's hard, at least for me, to get all the fuel out.

[Spidey]

Siphoning works to a point, but fuel tastes bad, and it's hard, at least for me, to get all the fuel out.

You know that they sell siphons that don't involve doing your best Castro-boy-toy impression, right E?

[DanTheMan]

Im not familiam with where the fuel filer is, but ive always drained mine through the pet cock

[enzo]

You know that they sell siphons that don't involve doing your best Castro-boy-toy impression, right E?

Psssht, that sounds like a stupid invenshun.

[connman]

I meant to update this thread a while ago and kept forgetting!

Long story short, I decided to just go for it and tear it apart myself - and the bike runs 110% better now! As soon as I pulled off the float bowls on the carb, I could see that our suspicions were right. Not only were most of the jets clogged to varying degrees, there were even little chunks of coagulated gas floating around in the chamber itself. Everything went pretty smoothly (except a stuck and then stripped screw on one of the float bowls, removed with a BFH by the nice guys at Monroe Motors down the street). The only moment that was a little scary came after putting it all back together and trying to start it again - it must have taken a full minute of turning it over before fuel found its way to the engine and it caught.

It seems to be running fine now through the whole range of the throttle. There is a little backfiring through the exhaust when it's warming up, but I don't know if that's to be expected? I don't think I mentioned this earlier in the thread, but it does have an aftermarket exhaust (Marving) which could affect that as well, right?

There's one more DIY thing that I really need to get done sooner rather than later, and that's fix my kickstand before the bike falls over. It looks like the PO tweaked it somehow because it's bent a bit and doesn't sit flush with the ground. Anyone have any suggestions on where to get a replacement, or who on the board has a vice, torch, hammer and some agression to work out? 

[Popeye the Sailor]

Did you do your belts?