unstable idle

[klmvtr]

hi all
new here and to firestorms

I have a 1998 firestorm and it has a rattle noise under 4k I have does the ccts and checked valve timimg
but the bike also has a rough/unstable idle, I have up the idle and it drops by about 500rpm and some times cuts out
I have servire the bike it has had new plugs, new air filter, I have balanced the carbs and adjusted the tps sensor to appox 520 ohms

if anyone can give me any pointers and advise would be good

many thanks karl

[agentpineapple]

Did you put the pipes on the underside of the fuel tank back on correctly?
Silly question but an easy mistake...

[klmvtr]

yeah I have had the tank off a couple of times now and checked and rechecked the pipe work
thanks

[lloydie]

i haven't seen a vtr with a smooth idle yet but 500rpm is a bit much . is your carbs seated and sealed correctly ?
any air leaks will upset the idle .

[klmvtr]

hi thanks for the reply
I haven't removed the carbs completely but there are no air leaks I can hear and all the pipe work is good

thanks karl

[Wicky]

What's the idle set at? Should be at approx 1,200. The VTR will occasionally have a carb fart where it will seem to hiccup followed by a stall - quite normal and better to have the idle a little high to keep it from stalling on the move. Otherwise you've done everything you can with TPS, new filter & plugs etc.

[klmvtr]

the idle is appox 1300 I had it up at 1500 but it still stalled on the odd time
thanks

[klmvtr]

just a update ive have the carbs apart and found the front cylinder choke seized part open, have cleaned the carbs and balanced bike seem to idle ok now

just a quick question if the timing was out on one cylinder would it still run okish but hold back higher up the revs

thanks karl

[AMCQ46]

If it runs great up to 7000 revs then won't pull through, then the timing on one cyl is 180deg out. A very common problem if someone has fixed a broken CCT

[klmvtr]

ok thanks for the reply
ill be adjusting the timing today as it is good up to 6500-7000

I done ccts but didn't set the timing first done the rear one ok but didn't move the crank and removed the front one and the timing jump
through I have got it right but my guess is it looking right on the marks but it 180 out

thanks for everyone`s help

[sirch345]

Follow one of these links for setting the valve timing:-

http://www.vtr1000.org/phpBB3/viewtopic.php?f=31&t=8326

http://www.vtr1000.org/phpBB3/viewtopic ... 18&t=31348

Chris.

[VTRDark]

through I have got it right but my guess is it looking right on the marks but it 180 out

I doubt it's jumped 180 out unless the cams where removed. If you have removed the tension while not on the compression stroke/chain not at the slackest point, then it would jump a few teeth. Hopefully not more than 3 or you will have bigger problems than a rough idle. I suggest you set the rear cylinder to TDC on the compression stroke, RT on the crank and cam lobes pointing upwards and inwards. Remove front cam cover and rotates the crank anticlockwise 1/1/4 turns until you come around to the FT mark for the second time on the crank. It passes once and then on the second time you see it you should be on the compression stroke (careful not to fall on the F mark). Verified compression stroke by the cam lobes pointing upwards and outwards. The opposite to the rear. You will most likely have to loosen the cam caps and slip the chain back around so the cam sprocket alignment marks all line up properly.

Read through the following:
http://www.vtr1000.org/phpBB3/viewtopic ... 31&t=28583

Sort your timing out properly first, then move on to carb tuning/idle issues. Not totally necessary but you may as well check your valve clearances while you at it. Both timing and valve clearances will affect how your carbs are tuned in.

What CCTS are you using. Have you fitted manuals or done a stopper mod?

(:-})