Lumpy runner!!

[peds]

I have a 2002 Tiger 955i, the bike runs fine when on choke (cold) but once warm the engine hunts and surges at low speed on minimum throttle (i.e. if sticking to the speed limits/cruising (PAH!)). The accelerator also becomes very sensitive (more like an on-off switch, if you are not EXTREMELY careful).

Acceleration is unhindered and smooth and fuel consumption is good.

Does anyone have any ideas please??

[iansoady]

Search here and on triumphrat for surging and you'll be overwhelmed with (mis?)information.

[NeilD]

yes, apparently "they all do that sir..."   have you just got the bike or has the problem recently started.. ?

[Chris Canning]

There's a trick to this surging/lumpy running your bikes,your  either on the throttle or off it there isn't any surging then.  :D

On a serous note( e'r thats fairly serious!!) find a decent dealer,that may be a problem,have for the latest map put in and ask to have the engine set up,they'll have done plenty,use that as your bench mark as a starting point.

[NeilD]

There's a trick to this surging/lumpy running your bikes,your  either on the throttle or off it there isn't any surging then.  :D

yep I had a go at that with mine tonight, and its fine on an empty road where you can tweek the throttle and sort of smooth it out, but a real pita in traffic..

[Chris Canning]

I've had mine 10 years now,untill I read threads on here it's not even something I think about,I went through another spell like this when the natives were restless on about the the hunting some years ago, and I went and bought an 02 sensor cost me all of 20 quid,and it all but stopped it,but I didn't like the way the motor ran,and too be honest it's rare for me to be in a situation of constant throttle(apart from 80 and above),because the only traffic I'm involved in is the stuff I'm overtaking,and thats a factual comment not sarcasm.

I'm happy to loan it too you to try,but to be honest it's a ball ache to fit on any 955 unless it's an 01,because they are just at the back of the motor and takes around 3 seconds,so a direct comparison is almost instint,were with the others it's a tank off job.

[peds]

yes, apparently "they all do that sir..."   have you just got the bike or has the problem recently started.. ?

I bought the bike about a month and a half ago to use as a commuter to work, and obviously, when I test rode the bike it was a) cold at first and b) I was new to the bike, and the place I tested it was rural with no traffic, so it didn't show up.

I suspect it may be the throttle position sensor because it pulls like a steam train with no hesitation or misfire.

Another problem I failed to mention earlier was if you 'blip' the throttle on idle it will stall almost every time, i.e at traffic lights etc.

[Chris Canning]

Like I said in the other post take it to a good dealer,have the bike set up,any dealer that has been around for a time will have dealt with many 955 engines,use that as your starting point,you haven't a snowballs chance in hell of sorting on your own when you don't even know the parameters of the bike,and like the vibration thread,get another Tiger owner to try your bike,but as we don't even know which country your in hardly likely to get any offers.

But if it's stalling there's def something that ain't right,although both my 885's and this 955 have a habit of starting wrong/oddly and I switch it off and start it again.

[KuzzinKenny]

Just a thought  :? do ya shut the Tigger down with the key or kill switch ??

it has to be with the key so the ECU can save the data !!

 :roll:

KK

[peds]

Just a thought  :? do ya shut the Tigger down with the key or kill switch ??

it has to be with the key so the ECU can save the data !!

 :roll:

KK

Always with the key, never use the kill switch on any bike........ apart from when you are stopped at traffic lights along side yer muckers and you hit theirs just as the lights change.....or is that just me??? Funny as hell!!!  :lol:  :lol:  :lol:

[Bixxer Bob]

I suspect it may be the throttle position sensor because it pulls like a steam train with no hesitation or misfire.

Another problem I failed to mention earlier was if you 'blip' the throttle on idle it will stall almost every time, i.e at traffic lights etc.

Don't jump in with the TPS.  I changed mine and it did improve things but I first proved it was U/S.  I've improved the surging on mine with a custom map and careful tweaking of the trims but it still has the odd hiccup.  The second fault you mention is almost certainly trims but Metalguru has done more work on trims that me so he's best placed to comment.

Try doing the 12 minute tune before you go spending any money; that may be all you need.  Search on here for how.

[cosmo]

Might be overthinking this, lads.  I just did sparking plugs and filter on my '06 (and removed the airbox restrictor), which lead to better power, no more surging, and easier starting. MPGs seem better, but I'm gettin' used to the power  

Not saying it couldn't be a number of other things, but plugs and filter are cheap, and it probably needs 'em anyway.

Cosmo

[metalguru]

yes, apparently "they all do that sir..."   have you just got the bike or has the problem recently started.. ?

I bought the bike about a month and a half ago to use as a commuter to work, and obviously, when I test rode the bike it was a) cold at first and b) I was new to the bike, and the place I tested it was rural with no traffic, so it didn't show up.

I suspect it may be the throttle position sensor because it pulls like a steam train with no hesitation or misfire.

Another problem I failed to mention earlier was if you 'blip' the throttle on idle it will stall almost every time, i.e at traffic lights etc.

This is the mistake a lot of people make (and governments) is assumption and it can end up costing a lot of money.
It is very difficult sometimes to pin- point a fault but the stalling is down to the IACV (Idle Air Control Valve) which will be gummed up or set wrongly. Along the same area you don't say if you have a scott oiler. the plumbing can cause problems as connected into the idle control pipes.
Best thing if you feel confident is to get an OBDII lead, a laptop and TuneEcu.
If not take it to the stealer you got it from and tell him it aint right and you want it fixed, quoting fit for purpose and all that.

[peds]

yes, apparently "they all do that sir..."   have you just got the bike or has the problem recently started.. ?

 Along the same area you don't say if you have a scott oiler. the plumbing can cause problems as connected into the idle control pipes.

Yes, I do have a scotoiler fitted however, the bike was like this before I fitted it. I made sure that all the connections were air tight and used self-amalgamating tape on the connections to ensure that they were.

I have not changed the plugs and filter yet but I may just pop down and get some anyway as although the service book is fully stamped, considering the 'ball-ache' it is to change these (battery out/tank off etc) whose to say that the previous owner was not ripped off as there are no invoices to justify the parts used.

I WILL get to the bottom of it eventually and I will keep you posted........

Thanks all for your help....

 :)

[metalguru]

OK this is good info.
When you next have the tank off, you get good at this, have a look at how tight the pipes are from the IACV to the inlet bodies and how clean the IACV port is. Because these engines run very lean any leak can lead to problems. If the IACV pipes are remotely loose or worn or out of shape replace them with 6mm silicon suitable for vacuum. The IACV unit is the triangular shaped thing under the air filter, make sure the port in the centre is clean and lube it with a little silicon or teflon spray, NOT WD40!! While you have the air box off have a look down the throttle bodies while opening the throttle an if you can see any gunge down there, this has to go. These are all jobs the stealers don't do on a service, and of course having got this far you can also change the plugs. If you can connect to tuneECU it would be a bonus to know what map you have, the year of bike and the exhaust type.