Author Topic: Low revs on Fazer (Read 6423 times)

dilboy · « **on:** 08 May 2015, 12:30:19 pm »

Hello all
Little problem, just bought a 2000 Fazer, had it serviced, new oil, plugs, air and oil filters. Taken it out and its really sluggish on low revs and back firing as well but not constant. Iridium Plugs set to.08.
We've not changed anything else.
Any ideas ?
cheers
dilboy

darrsi · « **Reply #1 on:** 08 May 2015, 01:04:05 pm »

Do a TPS check

Explained here......

http://foc-u.co.uk/index.php/topic,12294.msg136985.html#msg136985

dilboy · « **Reply #2 on:** 08 May 2015, 01:09:37 pm »

Cheers for that but you know what I'm going to ask, what's a TPS Check ?

darrsi · « **Reply #3 on:** 08 May 2015, 01:10:34 pm »

Yeah, i know, as above.

darrsi · « **Reply #4 on:** 08 May 2015, 01:32:14 pm »

A dodgy or non working TPS (throttle position sensor) can make the bike run badly, i have personal experience of this twice.

As you've just got it though, if the TPS is fine, then i'm gonna hazard a guess that a carb balance wouldn't go amiss, but that's much more involved.

It's really difficult to pinpoint problems when there's no maintenance history at all on a bike, because it could be anything.

andybesy · « **Reply #5 on:** 08 May 2015, 02:20:09 pm »

Did the problem only start after the service, or was it there before?

Fraser · « **Reply #6 on:** 08 May 2015, 05:20:54 pm »

Back fires would indicate un burnt fuel getting into the exhaust, ie some sort of spark plug misfire. if you changed the plugs you would obviously have had to pull off the plug caps, check that the ht leads are still tight in the caps, and just as a long shot, did you spray anything into/over the plug caps before refitting ? there are many products out there ie brake cleaner which leaves a conductive surface when it drys. perfect for causing misfires and back fires . The only safe product I've personnally found is WD40,

darrsi · « **Reply #7 on:** 09 May 2015, 10:11:55 am »

Just found this old post

http://foc-u.co.uk/index.php?topic=8367.0

darrsi · « **Reply #8 on:** 09 May 2015, 10:16:03 am »

Ignore this, my bad.

Fazerider · « **Reply #9 on:** 09 May 2015, 11:43:16 am »

That doesn't apply in this case, an FZS600 from 2000 is equipped with carburettors rather than fuel injection. All the TPS does is advance and retard the spark timing slightly.

darrsi · « **Reply #10 on:** 09 May 2015, 11:57:46 am »

Quote from: Fazerider on 09 May 2015, 11:43:16 am

That doesn't apply in this case, an FZS600 from 2000 is equipped with carburettors rather than fuel injection. All the TPS does is advance and retard the spark timing slightly.

Duly noted, and altered, cheers.

dilboy · « **Reply #11 on:** 09 May 2015, 03:28:37 pm »

Cheers for all the advice.
It didn't happen before the service
When changing the plugs I did not spray anything in.
I have just adjusted the tps and it sounds a lot better, revs are constant.
Will take it out later and or tomorrow and se how it is.

Balancing the carb, home job or at a professional to do it ?

cheers

darrsi · « **Reply #12 on:** 09 May 2015, 04:02:14 pm »

Quote from: dilboy on 09 May 2015, 03:28:37 pm

Cheers for all the advice.
It didn't happen before the service
When changing the plugs I did not spray anything in.
I have just adjusted the tps and it sounds a lot better, revs are constant.
Will take it out later and or tomorrow and se how it is.

Balancing the carb, home job or at a professional to do it ?

cheers

You need a carb balancing kit for starters, and obviously depends on your own confidence and ability?

Think i paid about £45 for a 2nd hand Morgan Carbtune kit, with the thought that mechanics around my way charge about £50-£60 an hour.

I've used it twice now so i'm quids in already, and the thing is once done the bike can feel soooo much smoother, especially at lower revs.
I did mine last week and my normally very noisy bike has noticably quietened a little bit, even though it wasn't too far out, but i can certainly feel a difference.
If it hasn't been checked for a long time, which is very possible, then the difference in running could be huge.

http://foc-u.co.uk/index.php/topic,91.0.html

dilboy · « **Reply #13 on:** 09 May 2015, 04:05:00 pm »

Cheers again for the help

Will get a kit and have a go

anutz · « **Reply #14 on:** 09 May 2015, 05:33:33 pm »

if ur gonna look at balancing...

here is what i used - you don't have to follow my trick of roping the tank up - i just could not get the fuel pipe off the tank...

roping it up did however mean i could just crack on....and not have to balance the tank on the seat back to front when i want to actually measure the vacuum.....

http://foc-u.co.uk/index.php/topic,15985.msg183713.html#msg183713v

I was concerned about the readings in terms of not being high enough, but its the sync that matters...

those carb vacuum port covers are tricky to get - needle nose pliers for their clips is a must.....and patience

there is also the question of how accurate the gauges are and if they are calibrated properly....i have no idea but i was happy eventually they all read reasonably close...

oh and read the scales the correct way as i did not initially!

dilboy · « **Reply #15 on:** 12 May 2015, 09:16:08 pm »

Well i took the bike to a local bike merchanic and stright away he said it was only running on 3 cylinders,so ive left it in his capable hands.

anutz · « **Reply #16 on:** 12 May 2015, 09:17:20 pm »

ah, lol, yes you need 4 ideally

dilboy · « **Reply #17 on:** 12 May 2015, 09:24:59 pm »

i guessed that when he looked at me with dismay

limax2 · « **Reply #18 on:** 12 May 2015, 09:36:28 pm »

If it was running o.k. before you did the service it could be that one of the new plugs was faulty. Not common but not unknown either. Or as someone already said a plug cap not pushed on fully.

dilboy · « **Reply #19 on:** 12 May 2015, 11:33:00 pm »

Thats was mentioned but left it with BURY BIKES hopefully back by the weekend

Fraser · « **Reply #20 on:** 13 May 2015, 04:56:47 pm »

Do they bury all the bikes or just for special customers !!!!!!!!!!

unfazed · « **Reply #21 on:** 14 May 2015, 05:47:09 pm »

Most likely the plug cap and wires.

Roll back the boots on the coil leads, unscrew the plug caps from the coil leads cut about 10mm off the end of the wire. Screw the plug caps back on until tight. Put some vaseline in around the top of the caps and the leads and roll the boot back on to the top of the plug caps.

dilboy · « **Reply #22 on:** 21 May 2015, 07:26:37 pm »

Well I had put the wrong caps on the plugs

and now it runs like a dream

Jules-C · « **Reply #23 on:** 21 May 2015, 07:47:17 pm »

Silly boy. But at least it's a cheap fix

anutz · « **Reply #24 on:** 21 May 2015, 10:53:36 pm »

how did you put the wrong caps on a set of spark plugs - not saying that in a funny way, i literally mean i did not even think about changing those things - i have seen custom ones, what was wong with yours, i thought as long as the coils were stock....

do different caps affect the spark plugs then?

I have seen different colors of leads as well...

assuming you had some of the wrong resistance or other propert?