Pointy fuel/engine issue

[BlackFlag94]

I've done a search for "pointy fuel issue" and found nothing so posting this thread... If you know of a thread with the information I'm after please post a link below.

I've recently had a brand new TPS fitted to my bike because my K3 pointy was dumping wads of fuel through and causing catastrophic bangs at random revs that made me sh!t bricks . As well as spitting flames out the back there was a stench of petrol. We'd fiddled with fuel mix and done a few other bits and bobs before changing the TPS. The guy who fitted the TPS calibrated it and all was well (only occasional pops and bangs in 3rd gear at approx. 4k). I was also told to run Redex for Petrol Injectors which I did and noticed a small drop in the amount of pops and bangs.

New problems... Occasionally below 5k the bike doesn't put fuel through and if it wasn't for moving, the engine would cut out. It also hesitates to accelerate sometimes at low revs before putting lots of fuel in which then causes a big bang next time the bike drops below 4k. I happen to know that my exhaust packing needs replacing as there isn't much in the can and I have no baffle in the end either.... But surely this isn't going to cause the problems I'm getting?!

Power commander or other varieties are not an option as I don't want to be spending more than £100 on it. I have outgrown the bike and am not in to throwing all my money at it to make it the bike I want it to be. I will be selling it once I'm 19 and can afford to insure a 600/750 s/s but want this bike to be running as sweet as I can make it.

Thanks for any help

[phil24_7]

You thought about giving it an ECU tune? Usually run at about £80-90 and should sort the fueling out for you. It is almost as good as a PCIII & tune on the SV.

[BlackFlag94]

Sounds good although permanent. Is there any danger involved with this?

[phil24_7]

None. It's a common way of tuning them. You see they come with a stock map, this is ok, but every bike will be slightly different so tuning this way will make it the way it should have been from the factory if they were to set each individual bike up properly!

Incidentally have you checked the calibration of the TPS? He may have moved it very slightly when doing everything up. I would check this first before doing anything else as it's free!

Instructions can be found here: http://forums.sv650.org/showthread.php?t=55459&highlight=ignition+live

[BlackFlag94]

Good shout.. will check the calibration. The mechanic is a mate so will get him to check it... "this rounds on me !!".

Am I right in thinking it's perminant? Also, will this increase my fuel consumption?

Thanks guys !!

[phil24_7]

The tune is permanent but as I said, it is how they should come from the factory but manufacturers do not have the time or finances to set each bike up individually so a compromise is met and a general map is put into the ECU's. It should actually improve performance AND fuel consumption so it's a no brainer really!

Regards

[mikerj]

The symptoms the OP has indicates an underlying problem that will not be cured by a custom remap or power commanders. Problems like this are most always down to a sensor or wiring/connector fault, though I'd also a check on the fuel pump and relay.

[phil24_7]

This is true, it may be that the TPS was a misdiagnosis and that just calibrating it properly has lessened the initial problem, though I wouldn't immediately point to wiring/sensor/connector fault. It could be any part of the ignition, ecu or fuelling circuits!

[BlackFlag94]

Oh yay... sounds like it could be a variety of things. Any suggestions where I should start looking?

[phil24_7]

Start with the TPS as that has just been fitted. Check it is correctly calibrated then we'll take it from there.

Are you sure there is something up with the bike? Are your cables adjusted properly? What about tick-over, is that set correctly?

V twins can also be a little snatchy/juddery at low revs and if you are new to bike riding it could be a lack of finesse in throttle control. In line 4's are much easier to accelerate smoothly. This won't be helped if your cables (throttle and clutch) aren't adjusted properly.

Most SV's with aftermarket exhausts pop and bang, it's one of the best things my bike does. After a decent run when I drop down to second, accelerate to around 4-4.5k thousand revs from 2-3k revs, back off...Bang!

So I guess I'm saying make sure everything is adjusted properly and then make sure you are applying the throttle smoothly and see how everything is then.

It may also be worth getting someone used to the SV (maybe a forum member) who is local have a little ride of it to see if there are any obvious issues.

Regards

[phil24_7]

PS. Fuel additives are a waste of money. If they were that good, fuel manufacturers would put them in the fuel!

[BlackFlag94]

It may also be worth getting someone used to the SV (maybe a forum member) who is local have a little ride of it to see if there are any obvious issues.

This is a good idea... Anyone you know from the gloucestershire area?

I've got 2 and a half years riding experience and have had this bike for over a year now... I know my rider skill has exceeded the capabilities of the suspension components (I have Hagon fork springs and 15W oil) and can feel the bike flexxing beneath me. I know what the bike is doing at anyone time but I cannot explain what has been happening lately.

There's deffinately something not right with fuelling or the engine. Idle seems to adjust itself... sometimes it's where I set it (around 1300RPM) and other times its down at 900. Also, the pistons feel like they're crashing sometimes, and from idle if I give the throttle a quick blip it sounds and feels like its hitting something. Valve clearances were adjusted 3500 miles ago. Its mainly this and the stench of fuel that has me worried. The jerkiness is mostly inconvenience but it is really putting me off my bike :/

On a slight sidenote... my bike's been burning oil for a while (put in another litre over the weekend)

[phil24_7]

Check all hoses as you may be leaking fuel. This would be causing under fuelling which could account for a few of your issues.

I haven't topped my SV up with more than a litre in 5 years (apart from servicing) so this will probably need investigating.

Regards

[Toooldtodie]

Had a problem with misfire and backfire, found it was due to a kinked rainwater drain from fuel filler which was then contaminating the fuel. Might be worth checking, dunno? As you said, the more suggestions, the more problems you can strike off the list.

[ophic]

I had a massive exhaust backfire problem, shockingly loud when coming down the revs under engine braking. It would go off like a shotgun at around 4k rpm and would make me jump out of my seat.

This was due to the dealership forgetting to re-fit the PAIR tube to the front cylinder after a valve check service.

Just mentioning as something to check as you seem to have reported the backfire in the same rev range.

[BlackFlag94]

Had a problem with misfire and backfire, found it was due to a kinked rainwater drain from fuel filler which was then contaminating the fuel. Might be worth checking, dunno? As you said, the more suggestions, the more problems you can strike off the list.

I've never heard about the rainwater drain.... what's that all about?! :confused:

I had a massive exhaust backfire problem, shockingly loud when coming down the revs under engine braking. It would go off like a shotgun at around 4k rpm and would make me jump out of my seat.

This was due to the dealership forgetting to re-fit the PAIR tube to the front cylinder after a valve check service.

Just mentioning as something to check as you seem to have reported the backfire in the same rev range.

That's probably what they did after my valve check as well then. I took it back and it sorted out that problem, but it still happens seemingly randomly (normally when I've been town riding)

Thanks for the suggestions guys !! Will checkout this drainwater thing...

[phil24_7]

Don't stress about the backfire, after market exhausts often cause this to happen and it is very unlikely to do damage unless it is happening a lot.

Regards

[ophic]

Don't stress about the backfire, after market exhausts often cause this to happen and it is very unlikely to do damage unless it is happening a lot.

There's backfires and backfires. Mine was so loud I'd still jump even when I was expecting it. It almost made me fall off decelerating for a motorway exit once.

[BlackFlag94]

After doing about 200 miles today, round town and country road blasts I think i've narrowed it down to dirt getting into the engine (from either air or fuel) and the TPS being incorrectly setup.

P.S. Anyone know roughly how much I'd get for my SV650S K3 with Hagon Progressive Fork Springs, R&G crash bungs and cotton reels, R&G Taily Tidy, Restrictor kit, Meta M357T-V2 alarm/immobiliser, 6000K Xenon Headlights and sidelights??? I'm probably going to get myself a 2009 ZX6R when I turn 19

[phil24_7]

Ophic - Was more talking about BlackFlags problems.

BlackFlag - It'll be worth more with the problem sorted, so try to get to the bottom of it.

Regards

[BlackFlag94]

TPS was calibrated 100% spot on.. changed spark plugs and seeing if this works.. Fingers crossed !!

[Bibio]

while changing the plugs check the coil connectors and all pair/airbox hoses plus the bungs on the vacuum points.

[BlackFlag94]

coil connectors....? The airbox was securely fastened when i checked

[yorkie_chris]

After doing about 200 miles today, round town and country road blasts I think i've narrowed it down to dirt getting into the engine (from either air or fuel) and the TPS being incorrectly setup.


Restrictor kit,

Got to question your findings there, how have you narrowed it down to this? I think you're barking well up the wrong forest.

What restrictor kit is it?


So to question your perception and logic on this score you seem to have attributed all problems to fuel being dumped into the bike or not. There is FAR more to the science of fuel mixtures and running engines than that, and it's pretty hard to tell just by listening.


Here's my two penneth, if you know what fault is... go fix it you don't need to ask us. Fact that you are asking says you don't. Tell symptoms don't try to tell the cause.

You say it stinks of fuel, it is fluctuating at idle and misfiring when you give it some load. I would say most likely it is plug or coil breaking down. Replace the plugs, see if you can swap coils with a mate one cylinder at a time and see if it sorts it.

[phil24_7]

What he said!

[BlackFlag94]

Fair comment... I know what a coil pack is on a car and tried looking for a similar looking thing on the SV but couldn't find anything. Does anyone have a picture or description of what and where I need to look for please?

The problems aren't consistent which is the most irritating thing which is why its taken as many miles as it has to establish this much. ****EDIT... It isn't misfiring on the way up the revs, only on the way down (this seems to have sorted itself out lately and after changing the plugs today it has only done it when i've given it a load of beans going up through the gears then let off in 4th or 5th, just one fart of a backfire then no more)

I will run a few more hundred miles and see what's new with the new plugs.

I don't have any mates with SV's, how much are they second hand or are they the sort of item you don't buy second hand?!

Apologies for being an **** Chris

[Bibio]

you have changed the plugs so it would have sorted it straight away.

are you certain that you have taken the nipples off the top of the plugs so there is only a thread showing (if they were present) pushed the plug caps fully home?

the sv plugs are very thin and it's very very easy to crack them due to over tightening them.

did the plugs go all the way in by hand then a nip up with a plug wrench or were they fairly hard to turn by hand and require you to use a plug wrench all or most of the way in?

yes the airbox might be connected but are all the relevant connectors and hoses coming from the airbox connected?

if you trace the thick black wire (HT lead) back from the plug you will find the coils.

if i were you i would get a compression test done.

[BlackFlag94]

I've had no issue at all with smell, pops/bangs (although I know these are to be expected a little with aftermarket exhausts), 'cutting out' briefly since changing the plugs but have only done 20 miles.

By nipple you mean the metal protector thing that screws onto the plug? If yes then yes I did

The rear plug went in all the way until needing to be nipped with a socket, the front did a sort of tight loose tight (the white part of the plug was mud coloured hence I feel the need to get myself a fender extender)

If memory serves me correctly there's just one hose from the airbox? It's connected at the airbox end but I dont' know where that leads to or if its connected at the other end. I've checked the inspection bubble and no fluid in there.

Thankyou, I will do this tomorow as well as the other bits I haven't done previous.

What would a compression test show me? (as in if I got a low/high reading?)

Thanks btw !!

[Bibio]

compression test will show if there is low compression in one/both of the cylinders this can help narrow down if you have a worn valve or worn bore etc.etc.

have you had your throttle bodies balanced?

[BlackFlag94]

Ah okay.. in which case its gonna be big money to fix it right?

I asked my mechanic about it then he had a little fiddle around and said I don't need it.. Should I ask him again?

[yorkie_chris]

I've had no issue at all with smell, pops/bangs (although I know these are to be expected a little with aftermarket exhausts), 'cutting out' briefly since changing the plugs but have only done 20 miles.

Solved then?

[BlackFlag94]

Hopefully... would seem weird that all these problems were just from needing new plugs. Just gonna sit it out for a couple of hundred miles and see if it happens again.

I checked that the coils were connected and they are, two seperate coils that are electronically connected ?!

Also took off the airbox to have a look inside, apart from finding a leaf the filter was pretty clean, took the filter out and had a look on the underside and there was a circular scorch mark on the underside. I think it was the front cylinder... Surely that isn't normal?! :confused:

[yorkie_chris]

If plug is crap sometimes it will spit back through the throttle body.

Yes 2 coils, 2 separate cylinders... is not like a car with distributor.

[jambo]

The rear plug went in all the way until needing to be nipped with a socket, the front did a sort of tight loose tight (the white part of the plug was mud coloured hence I feel the need to get myself a fender extender)


Can you double check this?

If the front plug isn't tightening properly, then it's possible the last one was loose. It's also possible the thread in the front cylinder head is not OK, in which case the problem may well come back.

Jambo

[BlackFlag94]

I just started to take the bike apart to check out various things that I've been advised to check such as seals between the cylinder and throttle bodies and to see if the butterfly valves operate at the same time for example and just give the bike a general going over to check everything is tip top.

In this link is a couple of pictures of things that I have found which I don't believe should be how they are and there is a video of the butterfly valves operating. Please just give them the once over and advise me on anything you can...

http://s1300.beta.photobucket.com/user/Cav-uK/library/SV650S%20K3

[Bibio]

what are you trying to ask?

do the top butterflies (STV) move when you start the bike?

do the top butterflies (STV) move when you rev the bike?

if answers to above are yes then yes that is what happens.

[BlackFlag94]

I've been told to check out the throttle body balencing and seeing if I could tell by looking at the butterfly valves.

They do both of those things you mentioned.

Also, the bike is still doing the misfiring thing at low revs where the engine has a slight pause where it doesn't have fuel or air going in. It feels like it isn't sparking but they're brand new plugs.

I just don't know what else could be causing this problem. Need someone to ride it for a few hundred miles and get their view on the issue. I thought it was slower but got 141 indicated earlier so don't think it is down on power

[Bibio]

a TB balance requires the use of vacuum gauges.