Poor starting and running

[Hyperopic]

Hi all, sorry for the long post, but I'm hoping by providing the info someone can help me out with some issues with my new bike.
I've just bought a 97 Firestorm with about 32000 miles on the clock off a friend of mine, and since it's about to start snowing up here, I thought I'd try and sort out a couple of the niggles he had with it.
Firstly, I was told it was awkward to start. With past experience of carbed bikes I knew there was sometimes a bit of a fiddle, but this one is horrendous! It needs precise choke setting and well timed flicks of the throttle. Not something I'm going to put up with. Also, he said it would sometimes run rough, particularly when the fuel was running low.
With both of these issues, my first thought was fueling. I removed the tank, the vacuum tap seemed to work fine, flow rate was good and apart from a few small flakes the strainer was relatively clean. However, there was definite rust colouration of the fuel sitting in the tap, so I decided to check the carbs. The air box was pretty clean, as was the filter, a standard stock one. Then I hit the first problem. Someone had the air box off previously, had seriously tightened the air duct screws, and stripped the head of one of them in the process. That had to be drilled out in the end.
Once in to the carbs, I was looking through the removal instructions and getting a bit confused. They referred to draining the coolant and removing hoses - but I couldn't find any hoses! It seems the carb heaters have both been disconnected, and the hoses at the water pump and thermostat cut and blocked off. Is this a normal modification and if so why?
Taking the carbs off, the retaining ring around the rear carb was on at an odd angle - not seated in the rubber, but partly overlapping the lower band on one side. Would this be enough to allow air in and screw up the mix on that cylinder?
Once into the carbs, I took the float chambers off. They seemed relatively clean - a thin, easily wiped off film of a rusty coloured fuel was all. The jets were clear, but both front and rear are fitted with 180 jets, with both pilot screws out about 2 1/8 turns. Would this be a reasonable setup with a standard filter and original cans?
That's as far as I got with the carb side of things at the moment. Finally though, I did check the CCTs, again from past experience with CBRs. Is it normal on the Firestorm to have oil leak out of the rear CCT after removing the bolt? Also, the rear CCT seemed to be at full extent, though it may just be the retract that's not working - the cam chain did seem properly tight. Given it looks like it could be original I think a replacement may be in order just in case.
Hopefully there's enough there for someone on here to help, but if you need anything else checked just let me know. I've probably got a few months now to sort it out before I'll need it on the road.
Thanks in advance :-)

--Richard

[Wicky]

Greetings

Think you're in for a long winter. From your description it could be corrosion from the tank combined with airleak on the intake side of things screwing things up. Which will all need rectifying* (come back to that in a bit...). No need to replace cam chain but look at replacing stock CCTs with a manual version (see workshop knowledgebase subforum) and while you've got the spanners out change the unfinned Regulator/*Rectifier for a later uprgraded finned version.

Hope you've got a toasty warm garage to work in!

[edds11]

welcome, purchase and refit the carb' heater pipes, not a normal mod' Iam aware of . unless its been raced, do this and refit the carbs and I think you will be halfway there. I haven't messed around with jets yet but it sounds like you know what your doing anyway, other guys on here will read your post and offer valuable advice....apart from that Carl guesser

[benny hedges]

first off - camchain tensioners.
avoid all the scare stories and fit a set of manual tensioners from here.
and follow the fitting guide in the workshop section - to the letter!
it is normal to lose a bit of oil from the rear - but not the front - thats why the front ones fail lol.

*dunt undo the tensioners unless the cylinder is at top dead, as described in the article in the workshop!!!
VERY IMPORTANT LOL!!!

thats that out of the way.

it may help to fit a fuel filter / strainer inline to prevent any crap getting in the carbs.

the heating hoses are not 100% essential - but tbh id refit them if i was you.

the starting problems.... check the obvious like plugs and air filter.
check for a good healthy spark from each plug.
the displaced clip / badly seated carbs definately wont help, as with any vacuum leaks from the inlet rubbers or vac hoses.
the float heights arent adjustable on these carbs so that wont be your problem - but it could well be that one or both of the choke plungers are sticking or not sealing properly.

what does the engine sound like when you get it running?
if the camchain tensioners have failed it will sound like a complete bag of fek!
hopefully the previous owner hasnt fiddled with them and bent a valve.... but all lbeing well it'll be sumat & nothing.

add your location to your profile as there may be someone close by who can take a look

[VTRDark]

It seems the carb heaters have both been disconnected, and the hoses at the water pump and thermostat cut and blocked off. Is this a normal modification and if so why?

It's not normal and the reason some people bypass them al together is just for convenience when removing carbs. Basically all they are is pre heaters to help warm the fuel mixture up in the carbs which helps with atomization in the cold weather. They should not make too much difference unless the weather is below freezing, but best to put them back on I would say.

Taking the carbs off, the retaining ring around the rear carb was on at an odd angle - not seated in the rubber, but partly overlapping the lower band on one side. Would this be enough to allow air in and screw up the mix on that cylinder?

Yes. What you need to remember is these are the biggest carbs that Honda produced and are very sensitive to tuning. They are not the easiest to tune spot on without going on a dyno.

The jets were clear, but both front and rear are fitted with 180 jets, with both pilot screws out about 2 1/8 turns. Would this be a reasonable setup with a standard filter and original cans?

I would say that is far too rich. As standard the mains should be 175 in the front and 178 rear Keihin jets. I would guess the needles are not standard as well if the mains have been changed. Also not that the emulsion tubes in the front and rear are different too. Here a usefull carb strip down thread for you http://www.vtr1000.org/phpBB3/viewtopic ... 77#p214203

Some links regarding the Cam Chain Tensioners (CCT's)

Standard CCT's can fail at any time and cause engine damage, it's a gamble!

You can either go for the stop mod http://www.vtr1000.org/phpBB3/viewtopic ... 31&t=19416 Which is the Honda auto CCT's that are converted to a fail safe. So when it does fail, it don't send the valves crashing.
Or
You go for the full manual conversion, your options are here http://www.vtr1000.org/phpBB3/viewtopic ... 16&t=22720

Then with regards to fitting View Topic View Topic http://www.vtr1000.org/phpBB3/viewtopic.php?f=31&t=8326

Hope that helps you somewhat and welcome to the forum.

That's just my guess


(:-})

[lloydie]

Hello and welcome to the forum and the the vtr .
With regards to the carb heater pipes .
If you ride in this cold weather reconnect them .
If you don't then don't worry about them .
I removed mine two years ago and it hasn't changed the way it runs .

A good carb clean and sync will help .
Wile you have the carbs of fit a front cylinder vac take off . It fits under the inlet :-)
Check the plugs are iridium as standard ones are not up to the challenge .
Check the nut and big cable on the starter motor for corrosion as this when cleaned up will help to get it started more easily .
And also set the tps to 500ohms after you have synced the carbs this too will help .
And fitting a 12a battery will get it to turn over better .

[tony.mon]

Hello and welcome to the forum and the the vtr .
With regards to the carb heater pipes .
If you ride in this cold weather reconnect them .
If you don't then don't worry about them .
I removed mine two years ago and it hasn't changed the way it runs .

A good carb clean and sync will help .
Wile you have the carbs of fit a front cylinder vac take off . It fits under the inlet :-)
Check the plugs are iridium as standard ones are not up to the challenge .
Check the nut and big cable on the starter motor for corrosion as this when cleaned up will help to get it started more easily .
And also set the tps to 500ohms after you have synced the carbs this too will help .
And fitting a 12a battery will get it to turn over better .

12Ah is standard, try fitting a 14 Ah battery.
Sounds like an air leak. What did the plugs tell you?

[lloydie]

I stand corrected thanks tony :-)

[benny hedges]

Sounds like an air leak. What did the plugs tell you?

indeed - and an air leak at the inlet = a vac leak as suggested.

the carbs work by vacuum so any leaks will seriously affect their operation, as the slides wont open properly and the fuel isnt drawn over the jets by the vacuum of the inlet air passing through the venturi, thus fking up the mixture.

and they are pretty sensitive at low rpm and idle.

[Hyperopic]

Thanks for the info everybody, looks like I've got some work to do!

For the CCTs I think I'll go for the Krieger manuals - had an APE one on a CBR600F and wasn't overly impressed with what I got for the money, or the colour.
Given I'm up in Inverness, where the weather can rarely be described as anything other than cold, the carb heaters will definitely be reconnected.
After reading through, I'm actually thinking of going down the lines of getting a complete salvage carb setup, since I'm needing to get needles, jets, water hoses and rear air duct (either broke in drilling out screw or was done by previous owners over zealous tightening). If I get a factory setup one, then at least I'm starting with a relatively known value, rather than whatever has been done to this one. Might be overkill to do that, but hopefully won't be too expensive. New carb to head rubbers seem to be in order as well.
Plugs look clean enough, but they were changed to Iridium ones recently by the previous owner, so won't give much of a clue to any fuel mix issues.
One other thing I did come across, the fuel pipes from the tank have been extended, with a 2-1-2 setup. Didn't look to affect flow any, but that'll get removed anyway. I take it that'll have been done to make work under the tank easier at some point. I've not done TPS adjustment before, is that just a case of loosening and rotating it with a multimeter attached?

Pilot screw adjuster turned up today, now all I need to find is my carbtune - it's been a few years since that was last needed! Thanks for the tip on fitting a vacuum take off, that'll save a lot of swearing.

[VTRDark]

Be careful buying carbs of ebay or somewhere as it's a bit of a lucky dip unless otherwise stated what the jetting is inside. Also be aware that the later (2001 onwards) carbs from the updated storms are slightly different because of the PAIR system that was installed.

Here's a link for the TPS http://www.vtr1000.org/phpBB3/viewtopic ... 22#p223114

And here's one for the extra vacuum take off http://www.vtr1000.org/phpBB3/viewtopic ... 31&t=18430 I purchased my parts direct from http://www.carbtune.co.uk/ I also purchased 2 extra brass nipples and rubber caps for the open ends instead of using a screws to cap hem off. This makes it far easier to attach the carbtune straight on as it's best to use the hoses that you have with the carbtune with the narrow tube (venturi) installed., otherwise you will have to squeeze the hoses to take an accurate reading.

(:-})

[darkember]

[quote="cybercarl"]Be careful buying carbs of ebay or somewhere as it's a bit of a lucky dip unless otherwise stated what the jetting is inside. Also be aware that the later (2001 onwards) carbs from the updated storms are slightly different because of the PAIR system that was installed.

The only difference will be one of the vacum pipes will have a tee off to supply the pair unit which is attached to the airbox. I stripped the whole lot out the other week.

[tony.mon]

I'd be tempted to leave the extended fuel lines in place, as long as they look big enough. You can always fit a quick disconnect (drybreak) in the line, and it makes balancing carbs much easier if you can just rotate the tank onto the seat and leave it connected.

[benny hedges]

I'd be tempted to leave the extended fuel lines in place,.

unless its kinking when the tank's in place or causing an airlock....
i had extended lines on mine and i found it was running out of fuel almost as soon as the fuel light came on.