Running problems return

My K4 has been running really well since I tested and reset all the sensors and linkages on my throttle bodies, however recently problems have been creeping back in.

I was out the country for a few weeks and then moved house so the bike was left without being started for about a month. It has now developed a few problems.

When I start the bike from cold it starts fine, but then slowly the revs die and it stalls (takes about 5-10 seconds to die). If I start it then right away hold the throttle on a bit it will run rough then all of a sudden it will clear and the revs suddenly rise, after this it won't stall.

After I have it started but it's still cold when I go to pull away as I let the clutch out and load the engine it will almost die, there is just no power there. If I twist on a little extra throttle it's ok to get pulled out but it's still down.

In general riding the bike feels down on power even when it is fully up to temp, it's not missing or anything, just lacking grunt.

Having been riding the bike regularly for a few weeks now it is running better but the problem is still there.

I'm going to go over the TPS again as that was the main problem last time but would appreciate any other ideas.

It feels like the timing/fueling is wrong as the bike doesn't miss at all and it's still smooth...

Thanks for any input!

Jynx

[andrewsmith]

the idle sound like it maybe low. Get it to temp and check the idle speed it should be 1300- 1500

which filling station do you use? as total used to make my curvy run like a bag of sh*te with similar issues

you may have cocked up the tps it maybe worth paying a mechanic to do it

Idle is ~1300 which is still a little high according to the TPS guide and the workshop manuals.

Have already been through a few different tanks of fuel so don't think it's that.

After I did all of the TPS adjustment last time it sorted all the running problems, and was running for 6 months, so I don't think I cocked it up. However my TPS was still out of spec by about 0.2v but after after taking to Suzuki service they didn't seem to think that would be a problem. I'm wondering if it has gone more out of tolerance and might need replacing.

Bike doesn't sound right either, it's not 'barking' like it normally does, sounds almost baffled - is this an indication of retarding timing? (and no I didn't put the baffle back in )

[andrewsmith]

you mean a bit fluffy. I would say the TPS is on it way and plead ignorance to the timing

Just to update this thread - this problem was probably caused by low fuel pressure due to a failing O-ring in the tank! It's taken me ages to find but I did a few months ago and all my random problems like this have now gone away!

I was going to suggest fuel pump but well done for finding it!