Help needed. Do I have a carb problem ?

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wyly
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Re: Help needed. Do I have a carb problem ?

Post by wyly »

JustMike wrote:Hi Wyly.
My mate suggested similar yesterday. So just waiting for him to finish work and give me the name of the stuff he uses.
There is always the possibility I have missed a bit of dirt and I`m like 98% there. So running some additives through the system might just finish the job.

Mike
Some of those orifices in the carbs are very, very tiny it doesn't take much for them to become restricted or obstructed. I had stumbling issues after coming out winter storage and I went through two tanks of fuel with Sea Foam added to each fill up before it cleared. Sea Foam does it's cleaning even when the bike isn't running. Restrictions may not be your issue but adding a cleaning additive is easy and it's inexpensive.

I try to remember to add it as a regular additive now once a month.
CBX a work in progress, still improving...GS1150EFE completed and awaiting modifications.....RD350, remnants in boxes scattered throughout the garage

JustMike
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Re: Help needed. Do I have a carb problem ?

Post by JustMike »

When I first put the bike on the road I put a couple of bottles of carb cleaner in the tank and although it helped it didn`t cure the misfire.
Now that I`ve stripped and cleaned the carbs and made definite improvements, if there is still a small blockage another dose of additive might help.
I still cant help feeing that it might be an electrical issue, but I`ll just have to explore all options until I find it.

Mike

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Re: Help needed. Do I have a carb problem ?

Post by JustMike »

Update.
Wyly, I bought a couple of cans of Seafoam to try and so far have seen no difference.
After doing my usual mucking about trying different things and getting nowhere quick I was getting ready to stick a camera down into the carbs to see if a slide was sticking with the engine running.
In the shed was nice and quiet and nobody outside making any noise and the neighbours dog wasn`t barking as it usually does.
On starting the bike I heard a noise which wasn`t normal. A strange sucking of air and an audible squeak suggesting it was a leaking manifold rubber. But I had already replaced them with new.
I grabbed a can of WD40 and sprayed it onto the No1 manifold and the engine spluttered. It continued to do this with every spray.
I loosened the clamps and moved the rubber which was nice and soft due to the heat and retightened the clamps. No difference.
I sprayed onto the air cut valve cover, more out of frustration. The engine reacted again. And did so with every squirt.
Cutting the amount of spray to the smallest amount I could still got a response from the engine.
While feeling around for a leak around the valve I noticed the sucking/squeeking sound was being reflected back up to me.
On closer inspection I found 2 holes under the valve where they have drilled into the carb body to create passageways and then plugged them.
When I sprayed onto these plugs I once again got a response from the engine.
So for a quick fix/test I put some rubber sealant onto the plugs to try and stop the leak and left it to dry.
On restarting the engine the leak appears to be gone.
But the engine is noticeably running cleaner and I can rev it up to 7,000rpm with no sign of a misfire.
Hopefully tomorrow will be a nice day and I can get the beast out for a run as that will be the only way to know if I have found the problem.
Has anyone ever come across these plugs leaking before and causing problems?
Luckily for me it is on the outside of the No1 carb saving me from having to haul them all out.

Mike

7845

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wyly
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Re: Help needed. Do I have a carb problem ?

Post by wyly »

amazing detective work! I don't know if I would've ever found that. :clap:
CBX a work in progress, still improving...GS1150EFE completed and awaiting modifications.....RD350, remnants in boxes scattered throughout the garage

JustMike
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Re: Help needed. Do I have a carb problem ?

Post by JustMike »

Never say never Wyly.
I took her out for a fast run yesterday and although there is still a little bit of roughness there the engine is running sweet.
Although I didn`t try in top gear she is red lining easily through the gears.
It`s a shame I have nowhere to load videos other than on facebook.
Also I`ve treated her to a set of 6 piston calipers which make a big difference.
Braking feels like with the standard calipers, but now there is no sponginess and if I need to I can put more pressure and you can then feel the extra braking power.
Using the original master cylinder I think helps stop them over powering the front wheel as I`m not getting any hints of the front wheel about to lock up on me.

Mike

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steve murdoch icoa #5322
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Re: Help needed. Do I have a carb problem ?

Post by steve murdoch icoa #5322 »

Mike, can you give us some more info on your new brake set-up. Maybe even start a new thread.
It would be great to know about the calipers, hangers, lines and master cylinder.

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Re: Help needed. Do I have a carb problem ?

Post by daves79x »

Were the little brass balls still in place in the cross-drilled holes? Was there evidence of someone trying to remove them? I've never heard, or has anyone I know heard of those leaking on their own. I'd put something more permanent in the plugs, like an epoxy or similar. Glad you found it!

Dave

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Re: Help needed. Do I have a carb problem ?

Post by JustMike »

steve murdoch icoa #5322 wrote:Mike, can you give us some more info on your new brake set-up. Maybe even start a new thread.
It would be great to know about the calipers, hangers, lines and master cylinder.
Certainly Steve.

Mike

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Re: Help needed. Do I have a carb problem ?

Post by JustMike »

daves79x wrote:Were the little brass balls still in place in the cross-drilled holes? Was there evidence of someone trying to remove them? I've never heard, or has anyone I know heard of those leaking on their own. I'd put something more permanent in the plugs, like an epoxy or similar. Glad you found it!

Dave
Hi Dave
To look at the carbs you wouldn`t know anything was wrong.
Elsewhere, on facebook I asked Jack of Old School Carbs if he had come across this on his travels to which he replied "once".
But the bike is running so much better now and I`m finally happy with it.
I only put some rubber sealant on the top of the balls and left it to set.
After taking it for a run yesterday I tried checking for air leaks again and nothing showed up, so I presume it is fixed.
Long may this continue. But I`ll be keeping an eye on it.

Mike

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Re: Help needed. Do I have a carb problem ?

Post by xtoolboxx »

Just bought my first CBX a lifetime dream however i think she is running rich she starts without the choke and runs sweetly. After sitting at tick over if i rev her she emits a puff of black smoke and clears, the exhaust pipes which are stainless are colouring a very pale yellow i did have a notion of lowering the needles one notch to see if that helps any thoughts would be greatly appreciated
Russell

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Re: Help needed. Do I have a carb problem ?

Post by daves79x »

Lots to consider. Does your bike have the stock airbox? What year is it? There are no adjustment clips on stock CBX needles, but if you found them, then it has an aftermarket jet kit. The bike will run best with the stock airbox and stock jetting.

Dave

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