Bike moving off with no throttle

Visitor Q · $25 whore Joined: 30 Apr 2004 Karma :

Just chucked in a new fuel pump, from a different model (possibly a vfr Rolling Eyes

) so required some bodging of the wiring (yay junction box and liquid metal).

Anyhew, all that happened before was the old one died, so the bike ran rough until it killed what was left in the carb inlet pipe.

However, just taken the bike out and it is acting like the choke is still on, in the sense that in first of second from stationery, letting out the clutch makes the bike move off (without touching the throttle).

Obviously this isn't the best of things.

Choke is fully off (at the lever, haven't checked the cable yet).

Idle is set low (1.5-2k, fiddled a bit but its not made much difference).

Throttle is working fine, although you have to close it manually (pretty much). But I don't think it's that.

What do you reckon? Gonna ride in to work tomorrow on it anyway as its a quiet sunday, but monday might be interesting. So wouldn't mind a few ideas to potter with tomorrow night.
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From September 2014 to January/February 2015 I will not be using any English, nor reading any. As such, I won't be on here. PM at will, but I won't be checking/posting unless in emergencies. Certainly not for the first couple of months. Please berate me savagely if I break that rule...

Robby · Dirty Old Man Joined: 16 May 2002 Karma :

I would assume that if it's chucking in far too much pressure then it'll overfuel, giving the impression of having the choke on.

See if it runs like a bag of arse warm. If it does, it's running rich. Also, if it starts easily from stone cold with no choke, then it's probably running rich.

lonner · Spanner Monkey Joined: 09 Jan 2009 Karma :

hi

idle speed should be 950-1100 on most bikes as 1500-2000 is way to high

alun111 · World Chat Champion Joined: 31 May 2007 Karma :

damz · World Chat Champion Joined: 15 Jul 2007 Karma :

Visitor Q · $25 whore Joined: 30 Apr 2004 Karma :

Rode the thing to london and back today. Bike seems a bit hesitant at times, like the chain is sticking. But only rarely and for short periods Thinking

Idle is set that high because it tends to ping about all over the place, and it gets higher when its warm Confused

The small amount of go when at closed throttle is abit dodgy round slow corners/roundabouts though, so could do with sorting it soon.
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China traffic/travel bike vid - When I make a sweeping statement, please add the word 'statistically' in to the sentence before you bitch...
From September 2014 to January/February 2015 I will not be using any English, nor reading any. As such, I won't be on here. PM at will, but I won't be checking/posting unless in emergencies. Certainly not for the first couple of months. Please berate me savagely if I break that rule...

alun111 · World Chat Champion Joined: 31 May 2007 Karma :

When was the last time you had your carbs balanced? This could cause a rough idle. Sort this problem out first instead of just setting your idle higher!
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Summer: '00 Honda CB600F Hornet
Winter: '93 Suzuki GSF 400 Bandit VP Variable Valve
Past Bikes: Lifan LF100-5 Lifan LF125-A Honda C70

lonner · Spanner Monkey Joined: 09 Jan 2009 Karma :

bit pointless trying to solve it realy as it sounds as though its a bodge all over.

good luck with it Thumbs Up

iooi · Super Spammer Joined: 14 Jan 2007 Karma :

Visitor Q · $25 whore Joined: 30 Apr 2004 Karma :

Have to take the carbs to bits to properly access the cable anyway Rolling Eyes

Joy.

And it's not a bodge /all/ over, just alot of it Laughing

Yes the carbs probably do need balancing, and its on my to-do-list along with valve clearances. Will probably wait until I have money and get a mechanic to do it.

Did have a thought though, if the old fuel pump was on its last legs, it might have countered a dirty air filter. Now its running well this would then mean it was getting enough air, hence rich. It would explain the occasional hesitance at high speed.

Used 15% less fuel today though Thinking

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China traffic/travel bike vid - When I make a sweeping statement, please add the word 'statistically' in to the sentence before you bitch...
From September 2014 to January/February 2015 I will not be using any English, nor reading any. As such, I won't be on here. PM at will, but I won't be checking/posting unless in emergencies. Certainly not for the first couple of months. Please berate me savagely if I break that rule...

AngelGrinder · World Chat Champion Joined: 09 Jun 2007 Karma :

I can get some vacuum gauges for carb balancing, so if you need them let me know...I might even be able to help if you havnt done it before.

Let me know!
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Currently Riding - 2002 Aprilia RSV1000 Mille

G · The Voice of Reason Joined: 02 Feb 2002 Karma :

I read this before and still don't quite understand - on some bikes its possible to pull away by slowly letting the clutch out. Definitely with an idle that high.

Pretty standard that you can do this in cars.

Visitor Q · $25 whore Joined: 30 Apr 2004 Karma :

damz · World Chat Champion Joined: 15 Jul 2007 Karma :

did you ever find out what caused this problem? my fzr has developed a similar problem and might be caused by the same thing
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Current Bikes RVF400 - 94
Cars: RX7 FD, Eunos Roadster
Former Bikes: FZR 250R 89, ZX7R 98

Robby · Dirty Old Man Joined: 16 May 2002 Karma :

I've got his bike in my garage while he's off in South Africa. The idle is still all over the place. I'm going to pop the spark plugs out today and see how they're looking, I'm hoping to see at least one cylinder indicating a lean burn, which would point to an inlet rubber leak.

I may also have to remove the carbs, although I hate doing that, to check for wear in the needle or jets, which could cause rough running.

Then there's the electrics. I'm not going to town on them. The reg/rec is fine, I might try the coils of my own CBR6 (same model, more or less) and see if they make a difference.

His clutch is fucked too. He shouldn't be allowed near bikes, it's like handing a box of hammers to a chimp on meth.

Visitor Q · $25 whore Joined: 30 Apr 2004 Karma :

Robby · Dirty Old Man Joined: 16 May 2002 Karma :

I'll try it on my fuel pump too, although I doubt that's a problem. Pickup coils can always be a possibility, but pretty unlikely and they mean taking off a side panel.

Not even thinking about the clutch yet. Externally it looks fine, so you may be right about shite springs.

Visitor Q · $25 whore Joined: 30 Apr 2004 Karma :

Are you equally amazed it didn't explode during my trips to work... or my horrific trip to drop it off to yours for that matter.

I'm very shocked. Very.

I wasn't exactly nursing it either Embarassed

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China traffic/travel bike vid - When I make a sweeping statement, please add the word 'statistically' in to the sentence before you bitch...
From September 2014 to January/February 2015 I will not be using any English, nor reading any. As such, I won't be on here. PM at will, but I won't be checking/posting unless in emergencies. Certainly not for the first couple of months. Please berate me savagely if I break that rule...