Running Problems

[IgorVigor]

Stripped the bike down today...

Checked the fuel tap diaphragm...
Thats OK.

Decided to take the carbs off and see if there was anything amiss...

Some moron had used some weird bright red flange sealant stuff on the float bowls..

took them off to find the main jet blocked up with some of the damn stuff...

have used a load of carb cleaner

The misfire is almost gone now

before it wouldnt rev past the 4500rpm mark unless stationary or a real handful of revs with the clutch in.
and it misfired like mad over that even stationary... (once the choke assembly had been replaced)

Now though, it will rev up to the redline (and touch the limiter if you dont pay attention :S)...

it still stutters a little around 7000rpm to about 8500rpm...
But the carbs aren't balanced... I have taken them apart, etc so they definately need balancing

When the front carb butterfly is opened fully, the rear carb butterfly has already gone past fully open, an starts to shut the other way...

Not sure whether I am going to make a homemade balancer or get local bike shop to do it :S

[benny hedges]

When the front carb butterfly is opened fully, the rear carb butterfly has already gone past fully open, an starts to shut the other way...
:S

that butterfly works the choke - the slides govern the airflow.
you need to look closely at the choke mechanism & how it's gone back together
have you got a manual?
if not copy the pdf manual from the workshop section

[Phil-VTwin]

errrr thats not right, the butterfly governs the air flow, which produces vacuum which lifts the slides to govern the fuel.

The choke doesnt move anything in the carb, it allows fuel to enter the engine via the holes at the top after the butterfly in the inlet side.

[benny hedges]

oh well, i stand corrected !
it still wants fixing tho. it's broke.

[Phil-VTwin]

It seems like Igor has almost cracked it

Next step, get them carbs balanced before trying anything else

[IgorVigor]

I still need to balance the carbs, I havent got the gauges and no local garages will do it today

I might see if I can tweak it a little just to see if it makes a difference...

I know they wont be perfectly balanced, but at least I could get them to open at the same time properly...

if once they are balanced properly, it doesnt cure it, I have got big problems :S

my reg/reg is fine (tested it charging)
there is a good spark to both cylinders
the stator windings are within resistance
the battery has a good voltage when bike isnt running

[IgorVigor]

Right, its not the carbs...

I have balanced them using the ear/tube technique and no matter how out of balance or balanced they are, the problem isnt solved.
And please dont moan at me for using the ear/tube technique...
I have extremely sensitive hearing and have used it to great success before..

The reg/rec is fine
the stator is fine
there is a good spark at both plugs (and I can guarantee its strong ) when the engine isnt running...
the fuel tap diaphragm is fine
the fuel tank filter is clean
the carbs are clean
the fuel in the tank is good.

So there must be a problem with the ignition circuit.
So from what I can see it must be one of the following (or combination of):
CDI (Bigger box by the back light)
Secondary CDI box thing (small box by back light)
Ignition pulser
Ignition Advancer
Coils

Any other ideas?

The bike runs ok up to around 7000rpm and then misfires like mad...
if stationary it will rev eventually to the redline
if moving it struggles to get to 7500rpm...

Got a good mind to get shot of the bike and get something smaller, and easier to work on...
VTR's were not designed for big stocky people to work on them :S

[tony.mon]

Get a mate round with another Storm, then play swapsies until you isolate the fault.

Oh, an check the TPS as well, Haynes manual has it covered.

[IgorVigor]

All very well unless its a problem that can damage the CDI etc...

Then I would have to buy a new box and not for my bike :S

The TPS was fine when I checked it the other day...

My patience with the bike is running thin though :S

[Phil-VTwin]

Just thinking out loud here.....

Your problem of "mis-firing" was first at 5000 rpm, you cleaned the carbs and it moved to 7500 rpm, now that seems to indicate to me it is not an ignition fault and the problem is still with the carbs.

[timber]

Hey Igorvigor

I have a similar problem with my bike, farting and choking around 3K the stalling. All i've done is change the air filter and had the fuel tank "repaired". Bike went fine before, now runs like s*!t.
Am in the process of cleaning the carbs, but if that does'nt work, i'm stumped.

Handy tip for anyone empying a full tank, syphon with a length of tubing, i use window washer tubing, which i also use for bleeding brakes! (not the same tube though, i'm not THAT mad) a length long enough to fit from the bottom of the tank to a jerry can (below the level of the tank) put inside the tank, preferably in the botton corner, suck until you see fluid coming past the bottom of the tank, then QUICKLY put the othar end into a jerry can! otherwise you get a mouthfull of petrol, NOT nice.

Any suggestions are welcome.

Thanks.

[sirch345]

Hey Igorvigor

I have a similar problem with my bike, farting and choking around 3K the stalling. All i've done is change the air filter and had the fuel tank "repaired". Bike went fine before, now runs like s*!t.
Am in the process of cleaning the carbs, but if that does'nt work, i'm stumped.

Any suggestions are welcome.

Thanks.

Have a read of this thread, this is the most common fault;-
http://www.vtr1000.org/phpBB3/viewtopic ... 05&start=0

Chris.

PS. Welcome aboard

[tony.mon]

suck until you see fluid coming past the bottom of the tank, then QUICKLY put the othar end into a jerry can! otherwise you get a mouthfull of petrol, NOT nice.

Any suggestions are welcome.

Thanks.

Try orange juice mixed with it.

[timber]

Well,

I took the carbs off, clean as a whistle! When re-fitting the choke cables noticed some play between the housing and cable slots.
Put everything back together, took her out for a quick thrashing (it's OK the neighbours didn't see ), and lo and behold she's running OK.
Still a "slight" inconsistancy in idle speed, which i'm guessing is due to the slack in the choke cables. Is it possible to get replacements with "adjusters" to take up any slack which will occur over time? (mountainbike gears have these to fine tune index gearing!)
It really is a mystery as to the cause, i can only guess that it was a kinked fuel hose, air lock or choke problem.

Cheers,

Timber

[Gerrit]

Try the following Igor, as I have been battling with my bikes misfire for months, and it seems to be a earth problem.

Connect a decent wire with spade connectors from the battery's neg. to the the earth on your Rectifier.

If the bike runs fine after this, you can start stripping and search for a earth problem.

Regards,
Gerrit