Ignition or fuel problem - new trixie owner needs help!!

[Norfolk Boy]

I have been looking for my first TRX for well over a year now and finally brought one off the internet a couple of weeks ago... (Will post some pics etc soon)

Unfortunately, it isn't running very well and it's certainly given me a crash course in mechanics and TRX body parts!

Scenario - Got it delivered, jumped on and rode quite nicely for 3 or 4 miles.. Then as the engine got warmer, the bike started to surge i.e. when holding steady at 4k rpm, it would feel like you are getting hit with gusts of head wind as the power came in and out.

As the bike got warmer the problem got worse.. most noticeably when you rolled off the throttle on approaching a car, and then opened up again to overtake. The front would dip as the bike decelerated / hesitated and then it would take off again. By the time i reached my destination (20mile ride) the bike's running was quite bad, with quite a lot of violent 'hesitation.

Summary of problem

Bike hesitates then picks up, especially when rolling on and off the throttle; but strangely enough it only seems to happen in 4th and 5th gear (I have tried my hardest to get it to
re-act in a bad way in all other gears with no apparent problems)

It gets worse the hotter the bike gets (in fact it's none existent for the first 5 /10mins of riding.

What I have done so far:

Checked spark plugs - running rich so changed plugs and dropped the jet needles one notch so they go further into the emulsion tube (result) no change in running so Fitted a K&N and put a few extra holes in the air box. (result) bike has gone from running rich to being 'weak' with no effect on the problem.

Decided that it must be an ignition problem, so visually checked all wires to and from the coil and got a local garage to check the coils/HT leads.. Other than cleaning up a few slightly corroded connections this threw nothing up and the bike is still running bad.

Anyone got any ideas ? could it be the Ignition unit / CDI ? Any help / thoughts would be most welcome..

[Mincehead]

It`s the carburation and the old TRX problem of emulsion tubes and needles.
You`ll need to get the carbs off and rebuild them or do what many owners(including me)do and replace the carbs with Keihin or Mikuni flatslides.
There`s loads of threads about FCR41`s(Keihins)and the emulsion tube/carb problems on here,the search facility at the foot of the index page will help you find them.

[idl1975]

Thoroughly cleaned the carbs yet? Could be water in the float chamber or crap partially blocking a jet.

Try replacing the emulsion tubes though. Does absolutely seem a distinct possibility - I would read up on the problem via the search function and see what you think.

My symptoms were basically increased fuel consumption, then power loss, then non-starting. Be aware that TRXs run rich anyway, so unless it's fouling its plugs (serious deposits/fouling on the plugs), that may not indicate an emulsion tube problem. May just be dirty carbs.

I have been looking for my first TRX for well over a year now and finally brought one off the internet a couple of weeks ago... (Will post some pics etc soon)

Unfortunately, it isn't running very well and it's certainly given me a crash course in mechanics and TRX body parts!

Scenario - Got it delivered, jumped on and rode quite nicely for 3 or 4 miles.. Then as the engine got warmer, the bike started to surge i.e. when holding steady at 4k rpm, it would feel like you are getting hit with gusts of head wind as the power came in and out.

As the bike got warmer the problem got worse.. most noticeably when you rolled off the throttle on approaching a car, and then opened up again to overtake. The front would dip as the bike decelerated / hesitated and then it would take off again. By the time i reached my destination (20mile ride) the bike's running was quite bad, with quite a lot of violent 'hesitation.

Summary of problem

Bike hesitates then picks up, especially when rolling on and off the throttle; but strangely enough it only seems to happen in 4th and 5th gear (I have tried my hardest to get it to
re-act in a bad way in all other gears with no apparent problems)

It gets worse the hotter the bike gets (in fact it's none existent for the first 5 /10mins of riding.

What I have done so far:

Checked spark plugs - running rich so changed plugs and dropped the jet needles one notch so they go further into the emulsion tube (result) no change in running so Fitted a K&N and put a few extra holes in the air box. (result) bike has gone from running rich to being 'weak' with no effect on the problem.

Decided that it must be an ignition problem, so visually checked all wires to and from the coil and got a local garage to check the coils/HT leads.. Other than cleaning up a few slightly corroded connections this threw nothing up and the bike is still running bad.

Anyone got any ideas ? could it be the Ignition unit / CDI ? Any help / thoughts would be most welcome..

[slow codger]

Whereabouts in Narfuk are you?? Not sure its the emulsion tubes if it starts easy after a run! is a carburation problem though, did you put the needles back after you changed the filter? as the K&N will make it run weaker, but you shouldn't have to change jetting.

Dave E

[idl1975]

Whereabouts in Narfuk are you?? Not sure its the emulsion tubes if it starts easy after a run! is a carburation problem though, did you put the needles back after you changed the filter? as the K&N will make it run weaker, but you shouldn't have to change jetting.

Dave E

Agree, not sure it is tubes if it starts fine, esp. if the plugs look OK. OTOH, the fact that trying to close up the emulsion tubes didn't fix the richness might mean it is ovalised ETs.

Dirty carbs or contaminated fuel in the float bowl can feel like a gear-dependent issue when it's actually load related (e.g. trying to pull a big gear + drag + big throttle opening). Try cleaning and drying the carbs thoroughly and draining the tank (run the hose into a jerry can on the ground and tap on prime). It would be relatively unusual (just IMO) for it to be CDI related, although there are usually one or two floating around on evilbay, or perhaps slow codger will come round and let you try his CDI...

I had similar symptoms to yours on my Duke - turned out to be water in the carb from wet cleaning. Harder to do on a TRX, but if the previous owner was a jet wash pervert, it could easily happen.

[Norfolk Boy]

Hi Guys - sorry for the late reply... I had to take a trip up to Newcastle for a few days.

I have now taken a fresh visual look at all the wiring, and made sure all the connections are tight, taken both emulsion tubes out for a look (I just looked at one before) and found an huge amount of Cr*p in the float chamber of the second carb which i didnt see before.

Both Tubes looked fine so i cleaned the chamber, dropped the needle back down again to help it run a bit richer (it was running a bit lean after i put the K&N on and put some holes in the air box) and put it all back together.

This has resulted in a 90% improvement ! but the annoying thing is, that i now dont know if it was as a result of playing with the wiring or cleaning the carbs, although my guess is with the carbs!

The only symptom it is displaying now appears to be when she's warm and your close the throttle, then whack it open again (i.e the kind of thing you would do when you roll up behind a car and then go for overtake) at this point she hesitates (drops power for a second) and then pulls through..

In my un-educated guess it would be either over fuelling, or an electrical problem at this point.

Slow Codger - Do I take it you are from Norfolk as well ? there doesnt seem to be many Trixies in this neck of the woods. I actually live on the Norfolk / Suffolk border - near Beccles

[Kayla]

The only symptom it is displaying now appears to be when she's warm and your close the throttle, then whack it open again (i.e the kind of thing you would do when you roll up behind a car and then go for overtake) at this point she hesitates (drops power for a second) and then pulls through..

In my un-educated guess it would be either over fuelling, or an electrical problem at this point.

Over (or under) fuelling. Drop a gear and keep it happy

[slow codger]

Sorry for late reply, been away for the bank holiday, I am in March, Cambridgeshire. Bit of a ride to yours.

Dave E

[idl1975]

Crap in one float chamber sort of sounds like the bike sat on the sidestand and one chamber dried up before the other. But try the mesh filter (IIRC) in the fuel tap - if it's contamination and not varnish, you may have residue in there.

Most likely is that the jetting is now a bit off because you have the needle on the wrong clip, the last owner changed the jetting, or it's the holes you stuck in the airbox (sorry). Sounds like it's rideable though, which is good.

Hi Guys - sorry for the late reply... I had to take a trip up to Newcastle for a few days.

I have now taken a fresh visual look at all the wiring, and made sure all the connections are tight, taken both emulsion tubes out for a look (I just looked at one before) and found an huge amount of Cr*p in the float chamber of the second carb which i didnt see before.

Both Tubes looked fine so i cleaned the chamber, dropped the needle back down again to help it run a bit richer (it was running a bit lean after i put the K&N on and put some holes in the air box) and put it all back together.

This has resulted in a 90% improvement ! but the annoying thing is, that i now dont know if it was as a result of playing with the wiring or cleaning the carbs, although my guess is with the carbs!

The only symptom it is displaying now appears to be when she's warm and your close the throttle, then whack it open again (i.e the kind of thing you would do when you roll up behind a car and then go for overtake) at this point she hesitates (drops power for a second) and then pulls through..

In my un-educated guess it would be either over fuelling, or an electrical problem at this point.

Slow Codger - Do I take it you are from Norfolk as well ? there doesnt seem to be many Trixies in this neck of the woods. I actually live on the Norfolk / Suffolk border - near Beccles

[dandywarhol]

Hi Guys - sorry for the late reply... I had to take a trip up to Newcastle for a few days.

I have now taken a fresh visual look at all the wiring, and made sure all the connections are tight, taken both emulsion tubes out for a look (I just looked at one before) and found an huge amount of Cr*p in the float chamber of the second carb which i didnt see before.

Both Tubes looked fine so i cleaned the chamber, dropped the needle back down again to help it run a bit richer (it was running a bit lean after i put the K&N on and put some holes in the air box) and put it all back together.

This has resulted in a 90% improvement ! but the annoying thing is, that i now dont know if it was as a result of playing with the wiring or cleaning the carbs, although my guess is with the carbs!

The only symptom it is displaying now appears to be when she's warm and your close the throttle, then whack it open again (i.e the kind of thing you would do when you roll up behind a car and then go for overtake) at this point she hesitates (drops power for a second) and then pulls through..

In my un-educated guess it would be either over fuelling, or an electrical problem at this point.

Slow Codger - Do I take it you are from Norfolk as well ? there doesnt seem to be many Trixies in this neck of the woods. I actually live on the Norfolk / Suffolk border - near Beccles

Dropping the needle weakens the mixture, not richens

If there's crap in the float bowl there's bound to be crap in the tiny filter in the "tee" piece feeding the carbs - unless someon's removed it

[Mincehead]

If I ever catch the petrol gnomes that crap in my fuel lines I`ll ferkin leather them!
Haven`t they got anything better to do?
I actually asked a guy whose ZRX12 had stopped on the A1 last summer this question;

Crap in the carbs mate?

The comical bugger replied,"i don`t think that`ll help it won`t run as it is"!

Great ice breaker,we both worked on it for about 40 minutes and eventually the water that had got into his block connectors under the tank was found,blown out(trying not to spit more moisture in)and the thing sprung back into life with a jump start off my old Rover.

[Norfolk Boy]

Well here's the latest...

I checked all wires again (DCI, coil and everything in between) making sure that everything was connected properly.

I then took the carbs apart again and, this time inspected both float chambers / emulsion tubes instead of just the one as i did before.. And as suggested by a few people there was a load of silt / cr*p in the second carbs float chamber ! I cleaned this out and raised both needles to increase the fuel flow (plugs were grey in colour). Then put it all back together again.

The test run, was 98% better ! and i could only get her to falter if i tried really hard - the best way to get her to re-act was to hit it hard through 2nd, 3rd and 4th, then into 5th and roll off the throttle to 'coast' then when i went back on the throttle it would drop power / hesitate and then pick up

I took her for a dyno test today, and results were:

74bhp to the rear wheel, good torque and BHP curves.

Apparently she's fueling a bit rich, but fairly consistent - with deviation from 11.6 Air / fuel ratio at its worse, to 12.85 at its best. I know this makes it sound like the graph was fairly flat, but it was up and down all over the place to look at. Summary is that it seems to over fuel at 3000, 5500, and 7000 rpm and be at its best around 3500 and 5000rpm

So it looks like the jets may have just been getting blocked by the crud in the float chamber. but I cant work out why I can still get her to faulter (When rolling off the throttle . From my limited knowledge of carbs, I suppose my maybe a pilot jet problem / idle mixture?

My other thought is that I cant remember seeing a filter in the T junction from the carb to the fuel pipe, so assume its been lost. Has anyone ever put an in-line filter on their bike ? as I cant see any type of fuel filter in place at all and assume I could be in danger of getting cr*p in there again?

I’m also considering stage 1 tuning kit, as it appears I'm running rich with the main jet needle adjusted ‘one up’ and too lean with it ‘one down’ so it looks like I could do with a different size jet.. Either that or say sod it and run her lean ?? or could this cause problems ?

[Mincehead]

Inline fuel filters work very well,you`ll find quite a few variations on the theme from any of the big names in aftermarket motorcycle spares and goodies.
You might like to plump for the glass bodied versions,I favour them myself,you can see when the filter gauze needs cleaning too.
As for setting up CV`s you might find this very useful:

http://www.factorypro.com/tech_tuning_p ... gines.html

I cleaned/rebuilt my own CV`s but have now decided to go down the flatslide route.
I`m glad you`ve managed to get 99% of your performance back,and that BHP reading really is pretty good for a motor supposed to make around 78 bhp at the crank.

[cobbadiggabuddyblooo]

When i first bought my TRX it was set up with staintunes and i put it on the dyno It came in at 70.6h/p...mmmmm..replaced needles and someone had put larger mainjets in.. (contacted staintune and pipes where designed to run on std jetting) and when back to std and new needles got 76/hp to the rear wheel...and from memory I think there is only two main jet sizes available for those carbs I was informed std and lots of gas.. But eventually went down the fcr flatslide route myself too..

[idl1975]

No, like most bikes no filter, but no reason not to use one. Demon Tweeks or e-bay will get you one cheap, then just pick your hose and drop it in. Won't stop fuel evaporation if you leave the bike for a long time, and o/c the TRX doesn't have an "off" setting on the fuel tap, so running the bowls dry is a bit of work - I suppose you could put a clamp on the fuel hose.

I would definitely go for a DJ kit. Not a huge expenditure, but the kit + a bit of setup by dyno blokey can really do wonders for fuelling and even manages the cliche of improved throttle response.

Well here's the latest...

I checked all wires again (DCI, coil and everything in between) making sure that everything was connected properly.

I then took the carbs apart again and, this time inspected both float chambers / emulsion tubes instead of just the one as i did before.. And as suggested by a few people there was a load of silt / cr*p in the second carbs float chamber ! I cleaned this out and raised both needles to increase the fuel flow (plugs were grey in colour). Then put it all back together again.

The test run, was 98% better ! and i could only get her to falter if i tried really hard - the best way to get her to re-act was to hit it hard through 2nd, 3rd and 4th, then into 5th and roll off the throttle to 'coast' then when i went back on the throttle it would drop power / hesitate and then pick up

I took her for a dyno test today, and results were:

74bhp to the rear wheel, good torque and BHP curves.

Apparently she's fueling a bit rich, but fairly consistent - with deviation from 11.6 Air / fuel ratio at its worse, to 12.85 at its best. I know this makes it sound like the graph was fairly flat, but it was up and down all over the place to look at. Summary is that it seems to over fuel at 3000, 5500, and 7000 rpm and be at its best around 3500 and 5000rpm

So it looks like the jets may have just been getting blocked by the crud in the float chamber. but I cant work out why I can still get her to faulter (When rolling off the throttle . From my limited knowledge of carbs, I suppose my maybe a pilot jet problem / idle mixture?

My other thought is that I cant remember seeing a filter in the T junction from the carb to the fuel pipe, so assume its been lost. Has anyone ever put an in-line filter on their bike ? as I cant see any type of fuel filter in place at all and assume I could be in danger of getting cr*p in there again?

I’m also considering stage 1 tuning kit, as it appears I'm running rich with the main jet needle adjusted ‘one up’ and too lean with it ‘one down’ so it looks like I could do with a different size jet.. Either that or say sod it and run her lean ?? or could this cause problems ?