Running problems/TPS issue?

[Flip]

Greetings fellow foccers.


Seem to have an issue with the better half's Fazer 600.  I had running problems low down on gentle throttle, which I diagnosed as carbs out of balance (my Fazer thou does similar stuff).  So I purchased the carbtune, and used the instructions on here to balance the carbs. 


First step on the destructions was to check/alter the TPS, so switched on ignition, disconnected TPS, reconnected and it read 10k (just over) so I figured I was in setup mode and it needed adjusting. Undid screws and turned it every which way but Sunday and it made f'all difference to the reading on the tacho.  I removed it completely, blew on it and looked at it REALLY hard, reassembled and there was a glimmer of hope as it briefly flicked to 5k and then 0k on the tacho, but then back up to 10k again.  Only the once though.  After that, every so often, when turning it back and forward, the needle might flick vagually toward 7k, but then back up to 10k again.  Please note, its not that I am able to get it to say 0k or 10k and just unable to find 5k - I cannot get it to say anything BUT 10k where-ever I stick the damn sensor. 


I tried to find how to get the tacho to report an error, it will give me an error of 3k if I disconnect the tps completely, but I figured that is normal?  Doesn't seem to give an error when the tps is connected.  Anyway - is it broke?


Second step was I stuck the tps in vaguely the same position, and slapped on the carbtune.  Balanced the carbs as best I could, but the readings were leaping around all over the place, eventually I found that holding the revs around 3k with one hand and altering the screws with the other seemed to work, and I got it close after a lot of swearing.  Reassembled and went for a ride, and its a lot better, but not quite right, I guess the tps isn't right?


Lastly, a very important note to people doing the same... RTFM.  After all of the above and packing the bike back in the garage feeling grumpy... I read the carbtune sheet, and they detail how to add the suppressors/absorbers into the carbtune rubber lines.  This would have given me a much better balanced set of carbs and would negate the daft throttle holding issue I had - oops!  If you are going through the same walkthrough, make sure you read the carbtune booklet and make your rubber tubes up correctly first!!

[Andy FZS]

Don't feel too bad I almost did exactly the same, but for some unexplained reason I read the instructions (not like me at all)

[Flip]

Haha - good, not just (nearly) me then!


Typical IT geek - rip open box of new toy, plug in - MAKE IT GO MAKE IT GO!  Scratch head, shout profanities at object, break it, send it back or sulk (or all of the above)... then read the instructions.

[red98]

sounds like a tps fault to me....where abouts are you,if your local i have a spare tps you can borrow if thats any help 

[Flip]

I'm in Surrey, near Camberley/Reading... are you anywhere nearby?   I was afraid it might be a tps error (


I found a link (bookmark at work, I'll post it up here tomorrow as it might help others) to a blog where someone went on a quest for an affordable alternative - I think he found the tps from an 850 adventurer fitted, I'll ge the model number, but it was barely into double figures to buy, as opposed to the £185 for the Fazer one, does that sound right?

[Gnasher]

You seem to have made a very common mistake and this could be your problem. 
 
When balancing the carbs the amount of Hg pulled by each carb is very important they must all pull 230 - 250mm Hg at 1150 - 1250 rpm.  This Hg reading sets the amount clearance on the butterfly which in turn gives you an idle speed and datum.  Before you start you MUST ensure the pilot screws are set correctly and that the rest of the engine is within spec i.e. air filter, plugs valve clearance etc.   When setting the Hg you my well have to increase or decrease the idle speed to keep it within the range, keeping them within the Hg range at the correct idle speed the whole thing is a balancing act hence the term "balancing". 
 
If yours are outside this range even just one of them you will get poor low speed running at small throttle openings the TPS will be useless, on a correctly set up bike you can disconnect the TPS and you wont notice any real difference to be honest.  Most bikes are not set correctly most stealers have no idea and use cheap untrained labour the same applies to DIY owners both taking little or no notice of Hg readings, most bikes I've worked on are all over the place.     
 
If after doing all the above you still can't set the TPS then it's possible its shot but that is easily checked by doing a resistance check.

[Flip]

OK, that makes some sense! I believe mine were in that range, but I didn't have the stablisers in the rubber tubes for the carb balancer, so it was very tricky to read!  I might have to go back in there and have another go, making a note of the readings I think, thank you!


Leading on from my previous comment about finding one cheaper, here is the post I found
http://www.bikesandtravels.co.uk/default.aspx?pagef=201&l1=Biking%20Blog%20FZS%20600%20Throttle%20Position%20Sensor%20-SOLVED!


A quick synopsis was that the TDM 850 had the same TPS and the Bandit 1200 might have been the same too - hopefully this might help other foccers if you've not stumbled across the article already

[Gnasher]

A TPS even brand new will do nothing if the carbs/idle/pilots screws are out you can sit there till the cows come home!
 
The TPS is nothing more than a first generation emission tool all it does is ensures the ECU uses the best one of the loaded ignition maps for a given throttle opening nothing more.
   

[red98]

great advise from gnasher  ....iam not far away.high wycombe.are you going to check the carbs again ? 

[Flip]

Well, this lunchtime I am going to have another go at balancing the carbs with the carbtune, as its working properly now, and the job is fairly easy.  Just did my thou and made that much better.


If we still have issues then I might well need to delve further - but this carb tweaking business seems like a black art to me, adjusting pilot jets and cleaning float chambers and the like.  Are you offering your fine services to assist, red98??

[red98]

hi flip.....have my hands full at moment with "the stuttering fazer" and working 7 days a week dos`nt help....have another go with the carbtune and let us know how you get on....theres some realy helpful people on here who know there stuff...we might be able to sort it on line  ....keep us updated  .......just read gnashers post again,great advice and worded so we can all understand....cheers gnasher 

[Rev Chris]

Great product. Purchased for my Yamaha FZS 600 Fazer (1999). It had been running very roughly (low revs, inconsistent tickover, low speed running, hesitation etc) since purchase in the spring of 2014. Did all the usual stuff - new plugs, checked plug caps,coils etc (all within spec) even purchased new TPS (ouch!) but problem remained. It was during a conversation with a mechanic that I found out that regular unleaded petrol had up to 10% Ethanol in it. Apparently it goes off after a month and leaves a residue particularly in the pilot jets (hence the poor low speed running). The bike was due to go into the garage for a carb cleaning session (about 2 hours labour ~£100). Read about Profi fuel (21 5* reviews on Amazon) so decided to give it a try. Took a third of the can (90mls) to the garage and filled up with Shell Vmax (less ethanol content) and filled the tank. Pleasantly surprised - running really well after 20 miles; by 50 miles engine is as sweet as a nut! Perfect low speed running, no hesitation and constant tickover. This product also stops the water content in the fuel rusting the tank during winter storage. If you are laying up your bike for the winter its probably better to drain the tank and run the carbs dry and fill up with fresh fuel next Spring. In summary - if you are experiencing poor running give this product a try first, rather than last - you could save a great deal of cash on unnecessary parts and labour costs.