help me troubleshoot my Storm

[Kurt999]

Yeah I breathed a huge sigh of relief, especially after the DO NOT START YOUR ENGINE warnings. Thing is I've wrenched on bikes for ages, all different types, and never had a problem. I just got myself into a vicious circle of doubting myself and chasing my tail. The fact that the fault occurred just after I fitted the MCCTs threw me. I find it hard sometimes to post things here in a logical order

Having taken a step back, taken a deep breath, drunk some beer and sobered up, I decided to take a fresh, careful look.

Reg/rec on, new battery from my other bike, still misfiring on the front cylinder. Front plug wet with fuel.

New plug in the front HT lead and it sparks like a good 'un

carbs off and looked into the intake tract and theres a puddle of fuel on top of the valves which just happened to be closed. So it looks like the front carb is dumping fuel in. I've had the carbs apart and everything looks ok, float valve is unworn and the floats aren't punctured. The slides rise and fall equally with a sucking/wooshing sound. And as per my previous post I have standard jets needles emulsion tubes all in the correct places checked against the Honda manual. I have 48 pilots (manual says 45) and the pilot screws anr now at 2 turns out front and 2 1/4 out rear. Standard exhaust and air filter.

Could a blocked air jet cause some sort of negative pressure that would cause extra fuel to be sucked past the float valve?

I'm running off an auxilliary tank through a tee piece into a fuel filter for each carb and I've remembered to block the vacuum pipe that activates the stock fuel tap.

[lloydie]

Are you trying to run it with the air box off the bike ?
And yes a blocked air jet will make it run very rich .
Especially the middle one .
Also have you checked the choke cables and plungers ?

[VTRDark]

carbs off and looked into the intake tract and theres a puddle of fuel on top of the valves which just happened to be closed. So it looks like the front carb is dumping fuel in.

I would check those float valves. It's really not a difficult thing to do. There's a little pin that holds the float in place which you can remove with a screwdriver and long nosed pliers. Use the screwdriver to push the pin out slightly, just enough to get at it with the long nosed and slide it fully out. Then slide the float off the top of the valve.

When putting back, I find it easier to slider the float onto the valve first and then slide the valve back into place while holding the float. Then use the long nosed piers again to slide the pin back in.

(:-})

[Kurt999]

Are you trying to run it with the air box off the bike ?
And yes a blocked air jet will make it run very rich .
Especially the middle one .
Also have you checked the choke cables and plungers ?

airbox on and bolted in position, with the velocity stacks in place, new oem filter, new sub filters and airbox lid on.

yes I've had the choke plungers out cleaned and reinstalled. Theyre moving freely.

[Kurt999]

carbs off and looked into the intake tract and theres a puddle of fuel on top of the valves which just happened to be closed. So it looks like the front carb is dumping fuel in.

I would check those float valves. It's really not a difficult thing to do. There's a little pin that holds the float in place which you can remove with a screwdriver and long nosed pliers. Use the screwdriver to push the pin out slightly, just enough to get at it with the long nosed and slide it fully out. Then slide the float off the top of the valve.

When putting back, I find it easier to slider the float onto the valve first and then slide the valve back into place while holding the float. Then use the long nosed piers again to slide the pin back in.

(:-})

I've already had the carbs apart and checked the float and float valve, as well as the float height. I don't think the problem lies there.

Just to confirm how many turns out on the pilot screws should I be with 48 pilot jets? I was 1 1/8 front and 1 1/4 rear. Someone on here suggested that this was not enough so I went to 2 front 2 1/4 rear and now the rear plug is wet with fuel when I pull it , whereas before it it was nice and dry. Honda manual says I should have 45 pilots, which I know alot of people change for 48s.

There's no extra holes in the slides or other signs of a jet kit

[VTRDark]

If you have a puddle of fuel sitting on the back of the valves inside the intake then it has to be getting past the float valve. It's either an issue with the petcock diaphragm so fuel is not shutting off, but the float should shut it off from going further and it will leak out the overflow, so I suspect the issue is the float/float valve/valve seat.

Have you checked the floats for any cracks or pinholes. Place them in some water and watch for any bubbles, bit like doing a puncture on a bicycle inner tube. Rare for a float to fail though so problem has to be the float valve and/or valve seat. The float valves have a pointed rubber tip that wears. You have missed something somewhere!

The float valve are a consumable item and should be changed, I would do this as a process of elimination, their not expensive and it will also improve how the float meters the fuel. While they are out inspect the seats and give them a clean with some carb cleaner. It's either that or try another set of carbs. Also check the petcock diaphragm. Quite common for these to fail and there was even a Honda recall on them.
http://vtr1000.org/phpBB3/viewtopic.php ... lit=recall

(:-})

[Kurt999]

If you have a puddle of fuel sitting on the back of the valves inside the intake then it has to be getting past the float valve. It's either an issue with the petcock diaphragm so fuel is not shutting off, but the float should shut it off from going further and it will leak out the overflow, so I suspect the issue is the float/float valve/valve seat.

Have you checked the floats for any cracks or pinholes. Place them in some water and watch for any bubbles, bit like doing a puncture on a bicycle inner tube. Rare for a float to fail though so problem has to be the float valve and/or valve seat. The float valves have a pointed rubber tip that wears. You have missed something somewhere!

The float valve are a consumable item and should be changed, I would do this as a process of elimination, their not expensive and it will also improve how the float meters the fuel. While they are out inspect the seats and give them a clean with some carb cleaner. It's either that or try another set of carbs. Also check the petcock diaphragm. Quite common for these to fail and there was even a Honda recall on them.
http://vtr1000.org/phpBB3/viewtopic.php ... lit=recall

(:-})

OK thanks I'll have another look. I looked at the valves and they looked fine, and I cleaned the seats with carb cleaner, but I'll have another go and change the valves. I checked the floats for fuel inside them, but I'll do the puncture test just to confirm. Deffo not the petcock as I'm running a small plastic tank that I use for balancing carbs.

[tony.mon]

And that's your problem. The standard tank has a vac operated tap that stops fuel flowing to the carbs when the engine is not running.
Your auxiliary tank is not fitted with a tap and therefore tries to feed fuel to the carbs even when the engine's off, and although the float needles stop fuel, it's not a perfect seal and some will seep past overnight.

It won't happen once you have your tank back on and the petrol vac tap is reconnected.

The fuel won't have stopped in the inlet tract, though, it will also have seeped past the inlet valves into the cylinder. It will then have flowed past the rings into the crankcases.
So an oil and filter change is now needed.

[Kurt999]

And that's your problem. The standard tank has a vac operated tap that stops fuel flowing to the carbs when the engine is not running.
Your auxiliary tank is not fitted with a tap and therefore tries to feed fuel to the carbs even when the engine's off, and although the float needles stop fuel, it's not a perfect seal and some will seep past overnight.

It won't happen once you have your tank back on and the petrol vac tap is reconnected.

The problem manifested itself when I was using the stock tank and fuel tap. I have just switched to using the plastic auxilliary tank as its easier to assemble and disassemble than messing about with the standard tank, and risking damaging the paint etc. It also allowed me to eliminate the tap as a source of the problem. My aux tank has 1 outlet, into a manual fuel tap, into a tee piece and then into 2 fuel filters, 1 connected to each fuel pipe to the carbs. I don't leave the aux tank connected overnight

The fuel won't have stopped in the inlet tract, though, it will also have seeped past the inlet valves into the cylinder. It will then have flowed past the rings into the crankcases.

my oil level hasn't changed and doesnt smell of fuel.
So an oil and filter change is now needed.

Following a carb strip (ie carbs empty of fuel), on starting the bike the misfire/wet plug symptoms reappeared immediately, even though I'd spun the motor over with the plugs out first to clear the cylinders. It has to be a fault in the front carb that I overlooked...what do you think??


Thanks to all as ever for your input and advice

[VTRDark]

It's back to the float/float valve again then isn't it. Strip the carbs right down. Float bowls off, floats and valves out, main jets, emulsion tubes, pilot jets out. Remove the fuel mixture screws being careful not to loose the springs, washer and rubber O ring on each of them. You may need a pick to get the O ring out otherwise it will blast out when carb cleaner is squirted in. Remove diaphragm caps, slides and needles. Remove the choke cables carefully (they snap easily!) undoing the Black plastic nuts that hold them into the carbs. That's the carbs stripped down enough.

Get some carb cleaning spray. I use the Wynns stuff from Halfords! and spray into every possible orifice you can see on the carbs. So that's through the the channels that the emulsion tube/main jet was in and the pilot jet and float valve. Then do through the fuel mixture screw channels (you should see this squirt out one of the holes in the side of the carb throat) While you there shove the straw in all the holes in the carb throat and squirt back through. Squirt through where the choke cables attached and down through all the air bleed holes on the top of the carb and also the hole the slide needle goes into. Basically the complete carbs, every orifice you can see. You may as well do through the coolant hose and fuel hose parts of the carb too.

Start rebuilding carbs. Make sure you put the emulsion tubes back in the right carbs as they differ. But before doing this you may want check these for wear ie have they stated to go an oval shape. Then give a good squirt through with carb cleaner. I find it best to put you finger over the end opening and then the cleaner fluid is forced out the pin holes.
http://www.vtr1000.org/phpBB3/viewtopic.php?f=9&t=25177
Same for the main jets and pilots.

Put new float valves in and put the floats back in. Don't forget to give the floats a good going over to check for any cracks or pin holes. Place in bucket of water to test for small leaks.
http://www.ebay.co.uk/itm/Honda-VTR1000 ... 1c403347af

Put the fuel mixture screws back in so that's rubber O ring, washer, spring and then the screw. Then the slide needle, slide, spring and caps. Make sure there are no pin holes in the slide diaphragms and be sure it's seated correctly. A smear of grease around the edge helps with seating it properly when putting the springs and caps back on.

Give the choke cables a good squirt of WD40 and move the cables up and down so it works it's way in and they operate smoothly. Smear a little grease on the little springs/plunger and then carefully tighten up the black plastic nuts. Do not overtighten these, go slowly and carefully. I find it easier if you remover the rubber elbow bit off the nuts first when removing or putting these back on. Then slide the rubber elbow bit back over the nut once tightened up. Also make sure you get the right one in the right carb as one has a shorter cable than the other.

You may want to give all the exterior moving parts/linkages of the carbs a squirt of WD or blob of grease too.

I think I've made that reasonabley clear and not missed anything.

Here's the base settings for jetting set up

STOCK SETTINGS
(as received from Honda)
Stock From Honda: Stock Filter/ Stock Exhaust / Stock Advancer
-Mains Jet Front 175 Rear 178
-Pilot Jet Front 45 Rear 45
-Fuel Screw (Turns Out) Front 3.0 Rear 2. 3/4
-Stock needles

With 48 Pilot jets
-Fuel Screw (Turns Out) Front 2.5 Rear 2. 1/4

Then balance carbs, go for quick ride to bring the bike up to running temp (if you can, I know your still waiting on the R/R) fine tune fuel mixture
http://www.vtr1000.org/phpBB3/viewtopic ... 14#p238528

Balance carbs again and you should be done.

Oh and you may want to wear gloves and some safety glasses. Carb cleaner is nasty stuff. It don't taste good and stings bad when you get it in your eyes.

(:-})

[VTRDark]

Another tip....when you have taken the jets and emulsion tubes out, leave them to soak in a puddle of carb cleaner in the bottom of the float bowls while you do the rest of the carbs. This will give both them and the base of the float bowls a good clean and get rid of any gumming and keep each carbs jets separated so they don't get mixed up. Try not to let rubber components soak in carb cleaner as it eats rubber.

(:-})

[tony.mon]

If fuel is filling the inlet tracts with the tank and tap in place check the overflow tubes (they just sit strapped together between the carbs) and make sure they are clear.
If it was fuel tap then the fuel will flow out of the overflow.

But fuel in the inlet tract suggests that the float needle is allowing fuel past it.
Even when you turn off a tap in the fuel line there is still fuel in the line that will try to push past the float needle due to gravity.
You could try swapping the float needle to the rear carb and see if the problem also transfers, then if so, buy a new needle.

[Kurt999]

If fuel is filling the inlet tracts with the tank and tap in place check the overflow tubes (they just sit strapped together between the carbs) and make sure they are clear.


If it was fuel tap then the fuel will flow out of the overflow.

No fuel coming out of the overflow with the standard tank and petcock or with the auxilliary tank. My overflow pipes point downwards. I can see in the manual how they are supposed to go. I don't think this will make any difference with though???

But fuel in the inlet tract suggests that the float needle is allowing fuel past it.
Even when you turn off a tap in the fuel line there is still fuel in the line that will try to push past the float needle due to gravity.

I totally agree, but the fault occured immediately after a carb strip and clean so It hadn't been sitting with fuel in at all

Although I see what you mean...you're not talking about fuel settling overnight and ending up in the crank cases, you mean a faulty float valve just allowing too much fuel through when the engine is running.

You could try swapping the float needle to the rear carb and see if the problem also transfers, then if so, buy a new needle.

I thought that today while I was mulling things over...great minds think alike and all that!!!

[Kurt999]

It's back to the float/float valve again then isn't it. Strip the carbs right down. Float bowls off, floats and valves out, main jets, emulsion tubes, pilot jets out. Remove the fuel mixture screws being careful not to loose the springs, washer and rubber O ring on each of them. You may need a pick to get the O ring out otherwise it will blast out when carb cleaner is squirted in. Remove diaphragm caps, slides and needles. Remove the choke cables carefully (they snap easily!) undoing the Black plastic nuts that hold them into the carbs. That's the carbs stripped down enough.

Get some carb cleaning spray. I use the Wynns stuff from Halfords! and spray into every possible orifice you can see on the carbs. So that's through the the channels that the emulsion tube/main jet was in and the pilot jet and float valve. Then do through the fuel mixture screw channels (you should see this squirt out one of the holes in the side of the carb throat) While you there shove the straw in all the holes in the carb throat and squirt back through. Squirt through where the choke cables attached and down through all the air bleed holes on the top of the carb and also the hole the slide needle goes into. Basically the complete carbs, every orifice you can see. You may as well do through the coolant hose and fuel hose parts of the carb too.

Start rebuilding carbs. Make sure you put the emulsion tubes back in the right carbs as they differ. But before doing this you may want check these for wear ie have they stated to go an oval shape. Then give a good squirt through with carb cleaner. I find it best to put you finger over the end opening and then the cleaner fluid is forced out the pin holes.
http://www.vtr1000.org/phpBB3/viewtopic.php?f=9&t=25177
Same for the main jets and pilots.

Put new float valves in and put the floats back in. Don't forget to give the floats a good going over to check for any cracks or pin holes. Place in bucket of water to test for small leaks.
http://www.ebay.co.uk/itm/Honda-VTR1000 ... 1c403347af

Put the fuel mixture screws back in so that's rubber O ring, washer, spring and then the screw. Then the slide needle, slide, spring and caps. Make sure there are no pin holes in the slide diaphragms and be sure it's seated correctly. A smear of grease around the edge helps with seating it properly when putting the springs and caps back on.

Give the choke cables a good squirt of WD40 and move the cables up and down so it works it's way in and they operate smoothly. Smear a little grease on the little springs/plunger and then carefully tighten up the black plastic nuts. Do not overtighten these, go slowly and carefully. I find it easier if you remover the rubber elbow bit off the nuts first when removing or putting these back on. Then slide the rubber elbow bit back over the nut once tightened up. Also make sure you get the right one in the right carb as one has a shorter cable than the other.

You may want to give all the exterior moving parts/linkages of the carbs a squirt of WD or blob of grease too.

I think I've made that reasonabley clear and not missed anything.

Here's the base settings for jetting set up

STOCK SETTINGS
(as received from Honda)
Stock From Honda: Stock Filter/ Stock Exhaust / Stock Advancer
-Mains Jet Front 175 Rear 178
-Pilot Jet Front 45 Rear 45
-Fuel Screw (Turns Out) Front 3.0 Rear 2. 3/4
-Stock needles

With 48 Pilot jets
-Fuel Screw (Turns Out) Front 2.5 Rear 2. 1/4

Then balance carbs, go for quick ride to bring the bike up to running temp (if you can, I know your still waiting on the R/R) fine tune fuel mixture
http://www.vtr1000.org/phpBB3/viewtopic ... 14#p238528

Balance carbs again and you should be done.

Oh and you may want to wear gloves and some safety glasses. Carb cleaner is nasty stuff. It don't taste good and stings bad when you get it in your eyes.

(:-})

Wow thanks for taking time to type all that out!!!

I've done pretty much all of that already, but I'll go back in and have another look and reclean everything. Stand by for loads of photos!!

I've ordered 2 new float valves anyway as I found OE ones on ebay at a cheap price. Apparently a mate of a mate has a complete set of VTR carbs in his stash box that I can have for parts and return what I don't use.

You say the pilot screws are 2.5 turns out front and 2 1/4 rear with 48 pilots. I thought the rear had to run richer so the rear screw should be out more than the front?

Cheers, I feel like I owe you guys

[VTRDark]

No worries I do go into one sometimes when I start writing posts. Maybe a little OTT.

You say the pilot screws are 2.5 turns out front and 2 1/4 rear with 48 pilots. I thought the rear had to run richer so the rear screw should be out more than the front?

That's what I first thought when I started tinkering with these carbs and I was always too rich. But if you look in the manual at the standard carb settings as I posted above, the rear fuel mixture screw is less. And anyhow the rear does run slightly richer. It has a bigger main jet and the slide needle is slightly longer. More fuel on the needle circuit equals less on the pilot circuit as some trickles through into the needle circuit. Measure the needles with a micrometer or vernier and you will see one is very slightly longer by a couple of thou. They also have different part numbers. That 2.5 and 2 1/4 is base point to start from, all bikes will be slightly different by roughly 1/2 to 1 turn depending on ware and tear, mods (exhaust and/or air filter in particular), climate etc etc hence the idle drop procedure for setting mixture. Watch that rev needle with a blip test too as this tells a lot.

As for swapping the float valves front and rear as a test as Tony suggests, yes not a bad a idea which will give you a rough idea, but be aware it's not exactly a precise test and it may leak anyway as the pointed rubber bit at the base of the valve wears into the shape of the seat it's used to working with. A thousand of a inch can make a difference when it comes to carb tuning just like with the slide needles.

Another reason I was running too rich when I first got my bike and started playing with the carbs was the float valves which I replaced. The old ones had worn around the rubber tip, like a ring which meant they sat lower in the seat and my float chamber was filling too much.

Here's an interesting snippet for you. You can get different floats for various altitudes. The majority of them when made are filled with air at atmospheric pressure at sea level (1 ATM). If you bought a float that was designed for a bike running at high altitude they would be filled with air at that altitudes air pressure.

(:-})