misfire/stutter at low revs

[RobH]

Hi all! Just bought a 95 Tiger and having some teething troubles. I bought the bike 'sight unseen' on Ebay (doh!) but I think it's probably worth it's money.

Had some much appreciated advice off a couple of the guys on the Yahoo tiger list and it seems I've probably got DAR. This is less of a problem to me than a nasty misfire/stutter under load at low revs. It clears up after 4000 revs and the bike pulls strongly from this point, it also idles ok (though noisy).

The guy selling the bike had to pay a dealer to get it running for him, apparently it had been standing for a while and taken on some water. I'm suspicious that there may still be water in the tank (and now the carbs) as the misfire is getting gradually worse since I picked the bike up. From previous experience it feels more like an ignition problem to me but the recent history of the bike suggests carbs...

To describe the symptoms a bit more clearly, 100 miles ago it was a barely noticeable miss, like one cylinder missed a beat, now it feels as though two are cutting out, sometimes simultaneously, for 0 to 4000 revs -...brrrr..er.e.er.e.err.e.errr.brrrrrrrr...you get the idea ;-)

Any advice greatly appreciated
Cheers
RobH

[Mustang]

sounds to me like it is the coils , 1 or two of em are going tits up .

Replace them with Nology's found here http://www.nologyhotwires.com/
you need the #152-001-060T PFC 06S single outlet  coils get three of em . they are 70 bucks each ( which is half the price of the shitty triumph ones)

Also the ignition pick sensor on the Right hand side crankshaft is a KNOWN failure item also . 70 bucks at the dealer / stealer.

resist the urge to mess with the carbs , as your problem is almost a sure bet going to be the coils and sensor .

Also get the valve clearances checked and or adjusted .
you don't mention mileage but if it has 20-30 k odds are the previous owner never had the valves done or even checked . valves will cause misfires too but they usually only rear their ugly head when bike is cold and then run ok to good when the operating temp comes up .

GET THE COILS FIRST ,you will be happy !, and as well as you are doing the coils do the sensor !
Do the valves second

[RobH]

Thanks for that, it does feel more like ignition from my experience, it's just the fact that it was full of water and is getting gradually worse that's making me suspect carb cr*p.

Sorry, should have said, it has 34K on it. Sprag has allegedly been done.

I checked the coils and leads out yesterday, one of the plug caps is definately bad, I deal with Magnecor so I'm thinking of getting a set built. I'm in the UK so I'm going to have to shop around for coils etc.

There is some noise from the top end (as well as probable DAR) so checking the valve clearances is on my list, I suspect the cam chain and tensioner, having heard similar from a couple of CBR1000s I've owned (these are prone to chain failure due to weak tensioner). I haven't found any mention of anyone having cam chain probs on here, are they generally reliable?

Cheers
RobH

[RobH]

Quick update, I can't ride a second hand bike without knowing it inside out so I've now pulled the carbs and found one of the airbox/carb joints was chewed up and pushed almost inside the box, the expansion ring inside was missing,  another was partially pushed into the airbox (bad seal), one of the carb rubber clamps was totally loose. All the carb rubbers are partially cracked, not split right through but could do with replacement. Choke wasn't operating smoothly. There's been a fuel filter fitted - it looks like the wrong way around, assuming the arrow point in the direction of flow...

It looks as though at least one coil is intermittent at best.

All this 'work' had been carried out shortly before I bought the bike at a cost of £350 ($600) and 8 hours labour - what a joke!! I'm in the wrong job.

I dread to think what I'm going to find inside the carbs...

Cheers

RobH

[John Stenhouse]

Rob, nology coils are available in the UK they have a supplier in Kent, check out their website, and follow the link

[Dr. Mordo]

Wow, it's a good thing you took it apart!

[aeronca]

wow, this must be an initiation when you but a steamer. seems like every one of us has gone through almost the exact same thing. but man, when you finaly work out all the problems, there an awsome ridding machine. just makes you want bitch slap the last owner for neglecting the bike so much .  keep us posted on the progress.      eric

[RobH]

Thanks for the support everyone!

Ok, I've dug a little deeper, carbs are now off, the recess that the main jet locates in was almost full of water on each bowl! There was also some other debris in there - think I've located the problem anyway! All the jets look a bit crusty so I'm going to give them a good clean out tomorrow before reassembly, will also flush the tank properly.

Aside from that, one of the tiny rubber o rings was missing from around one of the carb balancing vacuum outlets (beneath the diaphragm cap) and the seal on one of the float assemblies is mashed. I can't find these available on the fiche, it's the smaller of the two seals, don't tell me they only come with the float assembly!!?? :shock:

I may yet have to replace the coils, looks like one of them is relatively new anyway. I'm definately going to get Magnecor to build me some leads, once they have the pattern (they will copy mine) they will be generally available, probably about £30 for the set, I can keep them in stock if there's likely to be any interest.

Cheers

RobH

[Mustang]

Thanks for the support everyone!

Aside from that, one of the tiny rubber o rings was missing from around one of the carb balancing vacuum outlets (beneath the diaphragm cap) and the seal on one of the float assemblies is mashed. I can't find these available on the fiche, it's the smaller of the two seals, don't tell me they only come with the float assembly!!?? :shock:

Cheers

RobH

From Triumph Everything is a freakin assembly    the seal you speak of is really an oring and they are available from mcmaster carr but don't know if they ship to uk , but again they are just orings and you should be able to source something  .

http://tigertriple.com/forum/index.php/topic,4249

[offtheback]

Good to see you here Rob..  Since you already have everything off you might as well take out the alternator to see if the bolt on the alternator side is broken.  Look at Abruzzi's DAR post on what to look for if it is intact and you suspect the clutch side is making the noise..  Remember, do not pull too much..

[RobH]

Mcmaster won't ship to the UK but I've just ordered a pack of 50 (doh!) from a UK company, they're imperial measurements but should be pretty much identical in dimension. 3/16" ID 5/16" OD. Anyone needs any let me know - plenty spare!

Ordered up a load of bits to put the airbox and carbs etc back together properly, HT leads are on their way to Magnecor for copying (hopefully). Also got a can of air duster and a can of carb cleaner.

Will have a look at the alternator shortly...can't wait ;-)

Cheers

H

[nightrunner]

Rob,

Before you spend the money on new wires and coils, there is another way.  The TT600 uses coils that sit right on top of the plugs.  I picked up a used set of 4 for like $30 on ebay.  You just have to run extension wires (12 volt wire, not plug wire) from where the old coils mount over to the plugs.   So you upgrade to good coils and lose the need for plug wires in one fell swoop.  Between the coils and rejetting, my 98 runs great; including easy cold starts.

On the DAR, on the alternator side, the culprit is that the vane is able to jiggle a teeny tiny bit on its splines.  So as the engine cycles between accel and decel, the bolt on the end of the shafts gets tighter and tighter until it breaks.   Hardest part is getting the broken end out.  That alt is not cheap so be careful.  My fix was to use JB Weld on the splines to eliminate all slack, and to upgrade from DIN 10.9 to 12.9 bolt.  McMaster will sell you a box of them.  I'd send you a couple if your were a bit closer.

Cheers
Scott

[RobH]

Thanks Scott, that sounds like good advice, have you bolted the direct fire coils on somehow or do they just sit/rest on top of the plugs?? Do you know the manufacturer name and part number?

I've made progress with the DAR, mine was actually a loose drive shaft bolt on the clutch side, these things seem to fail in a variety of ways..At least my bolt can still be removed easily enough.

Cheers

RobH

[nightrunner]

Sorry I cant provide a part number.  They are factory coils.  I just went to ebay and found triumph coils for a TT600.  Triumph used two kinds of on-the-plug coils and they were used on more than one model.  One kind has flat top with mounting holes to bolt to valve cover.  These are too big to fit in the recesses on the Tiger.  The other kind are very skinny and fit nicely.  They just sit on the plugs.   Some folks make a nce little grommet to fill the gap.

There's always the Nologys if you are in a bind.  I had time to look for them and had not even heard about the Nology option.

[Mustang]

Sorry I cant provide a part number.  They are factory coils.  I just went to ebay and found triumph coils for a TT600.  Triumph used two kinds of on-the-plug coils and they were used on more than one model.  One kind has flat top with mounting holes to bolt to valve cover.  These are too big to fit in the recesses on the Tiger.  The other kind are very skinny and fit nicely.  They just sit on the plugs.   Some folks make a nce little grommet to fill the gap.

There's always the Nologys if you are in a bind.  I had time to look for them and had not even heard about the Nology option.

Nology Coils are plug and play no mods required and they work as good or better than anything you are going to adapt to the old girl !
Just sayin ..................