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748south
10th December 2009, 20:25
Ok so i'm riding home from work today doing 50km and all of a sudden the throttle goes dead, no power and the bike coasts to the side of the road, its done this a few times in te last couple of months so I pulled the tank off and replaced the original fuel filter and found the 2 breather hoses from the tank had been stuffed with masking tape, unblocked them and rode it 4o km each way to the burt munro races at Wyndhamwithout any problem, but it seems it's back. Anyone have the same problem before? its like the power switch was turned off but after stopping it fires right back up again

Guided_monkey
10th December 2009, 20:57
Sounds like you have already seen the answer.

Check the fuel tank vent and/or the fuel supply system.

Good luck

748south
10th December 2009, 20:58
Its been checked,but i'm thinking it may be a dodgy fuel pump or relay perhaps?

CookMySock
10th December 2009, 21:13
Is there any backfiring during the fault condition? Does the engine or exhaust smell hot? Does it only do it after a long ride, or on colder days? If you park the bike in the sun, does the tank build up pressure in it?

Any of these symptoms usually mean the tank breather is blocked.

Failing this, perhaps you have an electrical fault.

Steve

748south
11th December 2009, 07:15
No back firing, it just stops like you have turned the run switch off, as above i've replaced the fuel filter and unblocked the 2 breather hoses and thought that would fix it but it seems the problem is back again. (it has the new regulator rectifyer and a new battery too)

the more I think about it the more a stuffed fuel pump seems the likely culprit

mikeey01
11th December 2009, 08:19
Ducati electrics, gotta love em :)

imdying
11th December 2009, 08:35
Ducati electrics, gotta love em :)Hahahah that was my first guess... I suspect the fuel breathers etc are a red herring, and that being under the tank has disturbed some wiring. I'd be unclipping, cleaning, and applying dielectric grease to every connector as a next step. I'd also be looking for any worn insulation that is freaking the ecu out when it shorts. At least it hasn't fried it yet, that's something :)

748south
11th December 2009, 09:57
Perhaps i should buy a pack of sizzlers?

I was pretty carefull notn to dislodge anything when under the tank and this has been happening since before I had the tank out but I think you could be right about the red herring ay

glegge
11th December 2009, 10:11
Ok so i'm riding home from work today doing 50km and all of a sudden the throttle goes dead, no power and the bike coasts to the side of the road, its done this a few times in te last couple of months

Ducati you say? they do that. it's probably still running in. they do that from new, once the engine has completely bedded in, it will stop running at all, then time for a rebuild to start the unreliability all over again.
Enjoy your Ducati :innocent:

but seriously, The good ol 'where to look first' thing has always been if it's coughing and spluttering and then coming to a halt - fuel may be the problem (or lack there of), if it just cuts out (like you say it does), more likely to be an electrical fault.
may pay to check connectors to do with the ignition system - you know, unplug,plug back in the connectors to the coil/pickups, that kind of thing.
A good visual inspection of the wiring/connectors and any earth points as well. make sure nothing has broken or come unplugged or on the threshold of falling out of a electrical plug.
it's difficult to be sure, but if the fuel pump just fails, then you would think it would start to spit and fart then conk out as the fuel rail pressure drops, not 'just stop'
when it stops, if you try to restart straight away, does it run? if not, check for spark, if there is one at least it narrows it down to a fueling problem or if there is not to an ignition/spark problem.

Oh, check the fuel pump relay (I presume there will be one someplace), maybe remove and re-seat it.
Also - does the system have a way of displaying fault codes? this may point you in the right direction.

johan
11th December 2009, 10:46
I had a similar problem...

In my case it was the wires to the kill switch that had been pinched and worn and started to break the circuit every now and then.

It took me a while to figure that one out!

good luck

glegge
11th December 2009, 15:45
I had a similar problem...

In my case it was the wires to the kill switch that had been pinched and worn and started to break the circuit every now and then.

It took me a while to figure that one out!

good luck

well, there you go, a nice easy fix. i hope this is all the problem is with your bike too - best of luck - let us know how you get on ay.

748south
11th December 2009, 15:50
yeah i've got all sorts of things crossed, only had the bike 3 months and i'm pretty sure the place i got it from will cover it as it's been going on sonce the second week i had it, will keep you up to date, it will hopefully go up to them in Dunedin next week

748south
21st January 2010, 13:18
Just an update fellas, well after the fuel filter was replaced it ran sweet as for a couple of rides, and then it came back. So anyway I had the pipes all off her earlier this week to get them polished, refitted them and pushed it out into the drive last night, flicked the run switch on and....ah ha ....no fuel pump primeing, swapped the 2 relays under the tail and away she went, rode it to the servo last night sweet as! so just getting a replacment relay today, gota standard relay for $10 which will fit into the stock replay fitting off the bike, fingers crossed no more issues.