3000 rpm Shudder

[moose]

Hi All

I have posted this before, but as yet have not been able to resolve it and it's starting to bother me now.

Under load riding through 3000 rpm the bike seems to shudder below me.  I've checker wheel bearings and swing arm and they seem fine.  My brother who was following me one day without knowing of the problem im having even said it does not seem stable when accelerating.

It seems to be most noticable in high gears and happens through around 2500 and 3500 rpm.

Let me stress this is not a fizzy vibration, it really is more of a shudder  :shock:  

Any Ideas
Thanks as always

[KuzzinKenny]

Hey moose !! if its at that revs on matter what gear, it could be the FI !! there's a change of fueling about the 2500rpm and 3000rpm !! but i'll probably get shot down in flames by one of the real techy guys on here  :lol:

another thought, check you don't have any seized links on the chain, that would give you a shudder !!

good luck !!

KK

[AK Tiger]

Hi Moose.  I'll be following this topic very closely as my 2005 Girly does exactly the same thing.  The shudder/vibration (as good a term as any) starts at 2500 rpm and smooths out at 3000.  Gear selection makes no difference o mine, however.  You are right, it is very annoying.  It is so annoying that I'm considering taking the machine to ... shudder ... a dealer!

[SHROPSHIRELAD]

..............I posted this the other week but if you missed it this is how I get my Tiger running well again...........
I have recently joined the club but have had my 2003 955i with 16k miles and full stamped service history a while now and would like to share what I have learnt to get the bike running nice and smooth. When I first brought it home it was ridding like it was about to run out of fuel under low revs, it did not like running in any gear around the 2500-3500 rpms trying to hold a steady speed like 40mph in 6th gear was hard work. Took it to my local Triumph dealer in Telford to check the mapping as it has a TOR can and was told nothing was wrong this is how fuel injection triumph ride, which I thought was complete rubbish as I had ridden other Tigers and my brother 955i Daytona which was much better than my. I tried the o2 bypass plug which made no difference at all. I then took it to the new triumph dealer in Wolverhampton Stratestones and this is what they found....

1x fuel relay at £14.00
1x fuel filter at £30.84
1x throttle body gasket (gasket between injectors and head) £1.03
1x evaporative loss stepper motor £64.38
1x rubber grommet at £2.00
1x stepper motor housing (holder) at £22.29

Parts total £134.10, plus 2 hours labour £96, plus VAT £40.78

Basically the fuel relay was intermittent, the fuel filter required replacement, and the leaking gasket and broken stepper motor were causing mixture problems.

Well it has done the trick it will now run down to less than 2000 rpm in top gear with no problems ridding in traffic is now possbile, even if they did forget to reconnect a breather pipe back to the airbox which i found when cleaning the bike, also the overun popping sound from the exhaust has 100 % gone. A little tip If you do want an o2 senor buy them now I had to order one from Germany as no one seems to be selling them in the UK any more not even PDQ etc.

[Bixxer Bob]

What did they mean by evaprative loss stepper motor SL?

The only stepper motor I can think of is the IACV.  I thought only Californian models had the evaporative loss system?

Working from memory - which is not the most reliable - cos it's raining and the manual is out in the shed.... :roll:

[moose]

Shropshirelad...It seems that my symptoms are different than yours as im not struggling to keep the bike going or driving a in traffic at slow speed.  My dad was a mechanic (car), he had a listen and sys it is miss-firing at 2500 rpm and that would explain the shudder.  

So on that basis, I checked the resistance in the coils all three gave a reading of 1.0 ohm the book says they should be between 0.7 and 0.9 so I fugyre they are close enough and they are all the same.  I checked the resistance in the injectors, all of them measured 12.8 and 12.9 ohm's the book says they should be between 15.5 ohm's and 17 I THINK.  I know there are low but once again they are all identicle, so I figure the problem is not there.  Surely they all cant go together can they.  While I had te fuel rail off I cleaned the injectors with a cleaner and also added an injector cleaner into the fuel also.  As yet I still get a miss fire when riding and when revving to 2.5k at stand still.

What other causes could there be for my mis-fire, is it likely to be the injectors or could the throttle bodies need balancing, would that cause it, im running out of ideas not.  But thats the problem miss fire at 2.5k any ideas?

Please help  :(

[iansoady]

It sounds like the typical hesitation or stumble that is caused by the fuel injection system trying to dynamically "correct" the fuelling in that rev range.

Without going into great detail, the ECU looks at the reading from the O2 sensor and tries to change the air/fuel ratio delivered to the engine to achieve a target 14.5. This is known as closed loop running. On some bikes, this is unnoticeable; on others it is very evident.

Some people have had success with an O2 sensor eliminator which gives a constant "normal" reading to the ECU. I fixed mine by using Tuneboy (do a search here) and changing the air / fuel map so it doesn't try to do this "correction".

I believe the reason for the closed loop is to achieve emissions standards.

[Chris Canning]

It sounds like the typical hesitation or stumble that is caused by the fuel injection system trying to dynamically "correct" the fuelling in that rev range.

Without going into great detail, the ECU looks at the reading from the O2 sensor and tries to change the air/fuel ratio delivered to the engine to achieve a target 14.5. This is known as closed loop running. On some bikes, this is unnoticeable; on others it is very evident.

Some people have had success with an O2 sensor eliminator which gives a constant "normal" reading to the ECU. I fixed mine by using Tuneboy (do a search here) and changing the air / fuel map so it doesn't try to do this "correction".

I believe the reason for the closed loop is to achieve emissions standards.

Yep i'm thinking along the same lines,mine has never liked high gears at low speed,and with a 19t sprocket even less,if i do open the throttle and it's in a high gear does an awfull lot of shuddering,it's always been that way from new,i'd say it's very rare for me to use top gear unless i'm doing over 80mph.

[Timbox2]

Yep, Im on a 19 frt sprocket and 2500 is far too low for it to pull smoothly in the upper gears, I also get a sort of shudder if I try, but..........

I may also be looking at checking all the engine mountings and also the chain angle, not long after I put the new chain on I wasn't happy about the transmission whine etc and put a laser level up the chain, it was well out using the alignment marks and after tweaking the back wheel that also helped alot.

[moose]

But the funny thing is, if I go to top gear (6th) it does not do, I'm not getting loss of power, it's not like a wrong gear shudder.  It pulls hard through that range it just "Shudders"  :roll:

Am I correct in thinking that it is only the US bikes with an O2 sensor, im pretty sure that mine does not have one.  So will mybike still be doing what you say it's doing? :?

[Chris Canning]

Blimey!! they all have an 02 sensor,how is the ECU going to get the info to alter the fuelling when the motor is running.

Out of interest when the bike is shuddering,what happens when you change down a gear?.

[KuzzinKenny]

is this an ongoing thing...........

http://tigertriple.com/forum/index.php/topic,8082

 :icon_scratch

KK

[SHROPSHIRELAD]

I hope you get it running nice and smooth soon. I was thinking of selling my as it rode nothing like my old steamer Tiger.  Some times taking it to a trusted Triumph main dealer is the only way

[moose]

is this an ongoing thing...........

http://tigertriple.com/forum/index.php/topic,8082

icon_scratch

KK

Yes this is ongoing it has done this since I have had the bike, when I first got it being my first bike after passing my test I decided it was "character" but now it is bothering.

Blimey!! they all have an 02 sensor,how is the ECU going to get the info to alter the fuelling when the motor is running.

Please excuse my ignorance  :oops:  I'm not the most mechanically minded person  :?

But to answer your question, when it shudders...if I roll off the poer it will go away, if I dip the clutch it will go away, if I continue to accelerate through, it will go away.  When it comes it only lasts for about 1 to 1.5 seconds.

I balanced my throttle bodies yesterday and ity still does it, Im starting to think I should just live with it.  As this is my first EVER bike and being new to bikes (driven cars all my life) it might even be normal I dont know   :?

[TigerTrax]

Check your chain also.

My '98 Tiger had a 'shudder' when starting to move forward from a stop and on acceleration at slow speed. The culprit: Chain.  My DID530 had a some kind of stiffness in it that showed up at slow speeds.

You must inspect every link ... it is actually kind of difficult unless you loosen the axel and get alot of slack in the chain so you can work each link.