Idle drops on sidestand part 2

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arsey30
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Re: Idle drops on sidestand part 2

Post by arsey30 »

Revs not dropping, or dropping back slowly sounds weak.
Rich normally slow, heavy and rythmic.

Dave.
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Re: Idle drops on sidestand part 2

Post by oldgreyandslow »

arsey30 wrote:Revs not dropping, or dropping back slowly sounds weak.
Rich normally slow, heavy and rythmic.

Dave.
I'm pretty sure it was running rich, slow to pick up, when opening the throttle and letting it return it dropped below idle and then climbed back, but that was with it at 2.25 turns out on idle. Now back to 2 turns, however I need to check floats etc agian as the possibly aggressive installation attempts may have fecked everything up.
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Re: Idle drops on sidestand part 2

Post by oldgreyandslow »

Update - still not great

Refitted carbs, still a bit of a pain in the arse, but less so, used a couple of old dinner knives, but the fronts popped out a fair few times before I got them all in (at least I think they are)

Before fitting I did the following: Float heights checked, 2.5mm hole drilled, more carb cleaning, checked everything yet again, I think its OK. Fitted carbs as I mentioned above, no mallets, bits of wood etc, plenty of sweat though,

Started OK, got idle set, seemed a bit hesitatnt at times, not really bogging down but certainly not crisp.

Got everything nice and warm and its still not quite right, sometimes it was slow in coming back after opening the throttle and just shutting off, once or twice dropped back to 2k, sometimes below 1k before coming back to 1.5k so indicated being rich and lean????

Took it off the abba stand, started again, revs pretty much the same on the sidestand or vertical, but when warm and opened the throttle on the return to idle it got below 1.5k and cut out, restarted reset the idle, there's not much adjustment is there? and if you rev up to say 5-6k and release it falss back slowly and straight to 1.5k, vary the throttle a bit, say up tp 8k, blip it around a few times and then let it return it drops below 1.5k and comes back to 1.5k, its also a bit hesitatnt at very small throttle opening, almost stuttering once or twice

So the saga continues...........

Any ideas, suggestions welcome

Ta
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Re: Idle drops on sidestand part 2

Post by jetblack »

how is your ignition system? plugs? Leads?
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Re: Idle drops on sidestand part 2

Post by Neosophist »

Classic Rich symptoms

To quote FactoryPro
NOTE: A rich problem gets worse as the engine heats up.
If the throttle is lightly "blipped" at idle, and the rpm drops below the set idle speed, then rises up to the set idle speed, the low speed mixture screws are probably set too rich: try 1/2 turn in, to lean the idle mixture
Turn your pilot screws in a bit.

Start with a full turn rather than half a turn as you can always back them out.

IF you do get hanging too thats also an air-leak sign so make sure your carbs are seated well.
xivlia wrote:i dont go fast on this bike so really do not need a rear brake.. /
vic-vtrvfr wrote:Ask xivlia for help, he's tackled just about every problem u could think of...
oldgreyandslow
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Re: Idle drops on sidestand part 2

Post by oldgreyandslow »

Neosophist wrote:Classic Rich symptoms

Turn your pilot screws in a bit.

Start with a full turn rather than half a turn as you can always back them out.

IF you do get hanging too thats also an air-leak sign so make sure your carbs are seated well.
They are set at two turns out, as per the manual, isn't a full turn in likely to be a bit much?

Also is it possible to reach the pilot screws with the carbs on the bike, tank on etc?

I'll go get some more carb cleaner and spray around the rubbers to check for air leaks.

This is beginning to pi$$ me off!!!
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Re: Idle drops on sidestand part 2

Post by oldgreyandslow »

jetblack wrote:how is your ignition system? plugs? Leads?
New plugs, don't know about leads
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Re: Idle drops on sidestand part 2

Post by Neosophist »

oldgreyandslow wrote:
jetblack wrote:how is your ignition system? plugs? Leads?
New plugs, don't know about leads
Yep you can reach the pilot screws with a long flat screwdriver.

Start with a full turn!

This should make it lean and you get hanging revs..

The open the screws a half turn at a time
xivlia wrote:i dont go fast on this bike so really do not need a rear brake.. /
vic-vtrvfr wrote:Ask xivlia for help, he's tackled just about every problem u could think of...
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Re: Idle drops on sidestand part 2

Post by oldgreyandslow »

I've spent the day working on this sad pile of shite and I'm back to square one!

Wasn't 100% sure the carbs were seated correctly so took them off, turned the pilot screw in one half turn while I had them off, tried refitting carbs, still difficult, no blocks of wood or mallets but the fronts kept popping out when the rears went in, quite often I thought everything was fine, tightened the clips all round and the fronts came out again! FFS how difficult can it be????

I thought one of the rubbers didn't look like it was seating on the front left carb that well so swapped it with the rear, eventually got it fitted, at least I thought I had.


Started the bike, wasn't keen on running initially but sat at 4k with choke, let it warm, dropped choke off, set idle to 1.5k, blipped throttle a few times, revs drop back very slowly, below 1.5k and settle, so too rich?

Got long flat blade screwdrive wound pilot screws in a further quarter turn, started bike again, wouldn't settle to a decent idle, eventually got that OK, blipped throttle a few times, still dropping below 1.5k occaissionally, slow to return too, so tried yet another quarter turn, this is now one full turn back in from standard!

Still doing it and when really warm and the throttle is opened when it comes back its slow and drops below 1.5k hangs around 1k for a bit and stalls. Its hesitatnt on the throttle at small openings around 2-3k too.

Got it running again and thought I'd check to make sure there were no air leaks, sprayed carb cleaner, I really should get shares in the company making this stuff, rear two OK, front left OK, front right, spray cleaner revs rise, try again, revs fall and bike cuts out. Not sure if thats a leak/carb sealing issue or not, I suspect it is.

Now very very difficult to restart, won't hold an idle, and hang on, haven't I been here before???

So what next, apart from throwing the entire fecking heap of shite in the skip?

I'm beginning to think new or reconn'ed carbs, GF does some for £80, at least then I'd know they were set right, but could it be something else I'm missing?

Can the above be explained by a possible air leak/front right cab not seating right?
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Re: Idle drops on sidestand part 2

Post by Neosophist »

Yes.

If its' leaking air.. as described by your carb-cleaner affecting the revs you'll get inconsisten rich / lean mixture symptoms.

You'll also NEVER get a good idle.

Pilot screws back to standard and make sure you have a 100% seal on all the carbs before you do any investigating :-)

You'll get there.

Carbs sound ok.. just letting in too much air.
xivlia wrote:i dont go fast on this bike so really do not need a rear brake.. /
vic-vtrvfr wrote:Ask xivlia for help, he's tackled just about every problem u could think of...

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