Hi all, The other day I couldn’t start my bike when it was hot, happens Often enough but this time was the worst, so I’ve gone to investigate the fuel system. The bike does also cut out or splutter at approximately 6 and 14 thousand rpm. The first thing I’m checking is that there’s no major blockages in fuel/vacuum. I’ve noticed that the hose underneath the fuel tank doesn’t allow any air through if I either blow or suck through it. I assume this is a breather and should indeed allow air through? can anyone confirm this and also give any other ideas. Cheers
That would be the drain hose for water or fuel overflow under the cap setup .... there will be a steel tube running thru the tank and the opening u will see if u unbolt and remove the fuel cap as a whole If its blocked then there could be crud or rust under the cap assembly Also the breather for the tank is in the cap setup and if its blocked then u will get a vacuum which stops/slows the fuel flow The non start when hot could also be valves need doing and the splutter could be carbs needing an overhaul
Thankyou for the information, I’ll take a further look at the overflow setup then as it’s definitely blocked. The hot start issue seems to be intermittent, I’ve been on rides where it’s just fine and others where it’s bad. I remember now that last time it happened I switched to reserve fuel and it started right up, although I had plenty of fuel in the tank. The stuttering issue also seems intermittent as sometimes it pulls beautifully. The intermittent nature has me thinking that its a fuel supply issue
There will be internal filters on the fuel tap .... apart from filtering they give u the "on" and "reserve" levels .... they may be somewhat blocked
Thankyou, I’ll have a look at them, might just get a new fuel tap as the current one looks quite old and passed it’s used by date
Make sure the vent is clear. If not it will starve as a vacuum is created in the tank and less/no fuel will flow. When it's giving you trouble, pop the fuel cap and try again. If it's instantly better, there's your culprit. Compressed air through the vent under the cap will usually sort it out. If it's truly blocked you'll have to dig all the crap out of it manually. Had to do that on quite a few plastic ducati fuel tanks.
I’ll do some further investigation, I’m hoping it’s just a fuel delivery issues either way. Don’t wanna take off the carbs if I don’t have to. Thanks for the info mate
That crud that is under the tank looks more like tank liner that has been put on the outside to try and seal up rust hole leaks.... I am not sure that tank is going to last too long from the look of it.
Yes unfortunately I think you’re right, there does appear to be rust down the bottom of the tank. Not ideal