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odd things happening

Fuel System: Gas (Petrol) tanks, Carburators
Macgyver5
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odd things happening

Post by Macgyver5 » Tue Sep 14, 2010 8:25 am

So first it's a 1964 Honda Super Hawk... ok I have put my carbs back on freed the slides and got the bike to start, but now the idle wants to jump to 4-6k then come back down slowly or sometimes not at all... if it does come back down to say 1k then if I try to give it gas... even just a millimeter it jumps back up to 4-6k... any ideas?

Brandon

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davomoto
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Post by davomoto » Tue Sep 14, 2010 8:34 am

Did you sync the slides? make sure they rise at the same time. Check for air leaks around intake flanges. Did you do Eds' tune up ?
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LOUD MOUSE
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Re: odd things happening

Post by LOUD MOUSE » Tue Sep 14, 2010 8:34 am

Ya have one slide higher than the other and it is running more on one cylinder than the other.
Make sure the slides are coming off bottom at exactly the same time then adjust them a small turn of the needle at a time.
A sort of quick way to find the higher slide is to find the side with the less heat/pulse at the exhaust and turn it in.
If the engine starts to race then turn it out to where ya started and turn out the other as it is the slide which is to high.
May take some time to get it correct as this is new to ya but ya can get it by listening to the exhaust pulse. ..........lm

Macgyver5 wrote:So first it's a 1964 Honda Super Hawk... ok I have put my carbs back on freed the slides and got the bike to start, but now the idle wants to jump to 4-6k then come back down slowly or sometimes not at all... if it does come back down to say 1k then if I try to give it gas... even just a millimeter it jumps back up to 4-6k... any ideas?

Brandon
Last edited by LOUD MOUSE on Tue Sep 14, 2010 9:18 am, edited 2 times in total.

Wilf
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Post by Wilf » Tue Sep 14, 2010 8:53 am

My bike did exactly that when I first got it running. It was caused by a worn centrifugal advance and was cured by replacing it with a good used one from LM. Stretched or broken advance springs would have the same effect.

If this is the case, there should be a noticeable clatter in the top end from the advance arms flopping around.

Wilf

Macgyver5
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Post by Macgyver5 » Tue Sep 14, 2010 12:29 pm

There is quite a bit more clatter at the top end... I will check on both... is there a way to trouble shoot the advance springs or the system? And Ed I have been wondering something... is there anything in the carb that can't withstand the Berrymans Chem dip? I don't want to ruin any internal rubber, and I think a few days in the chem dip can will do them good.... Also I thought I read a way to measure the floats with a machinist's ruler to determine if they were equal? I haven't touched any of the internals since you set them.

B

Wilf
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Post by Wilf » Tue Sep 14, 2010 12:56 pm

I can only think of two ways at the moment. Use a timing light to see whether the marks on the rotor "float" around at idle for no good reason, or pull the top off the head to visually inspect the advance mechanism. There may be a third test, but that eludes me right now.

I think I remember an earlier post "advance unit springs" where I talked about measuring the free rotation of the points shaft.

I hope this is of some help.

Wilf

LOUD MOUSE
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Post by LOUD MOUSE » Tue Sep 14, 2010 10:26 pm

Ya ask a good question as to cleaning the carbs.
About 1965 HONDA used a NYLON slide guide.
If ya leave the parts in the cleaner more than an hour or so the NYLON can/may soften and ruin the body for use.
I set the floats when I can see the bottom is in a direct line with the jet location and the jet is removed and the float tab is first touching the needle pin and not compressing it. ........lm
Macgyver5 wrote:There is quite a bit more clatter at the top end... I will check on both... is there a way to trouble shoot the advance springs or the system? And Ed I have been wondering something... is there anything in the carb that can't withstand the Berrymans Chem dip? I don't want to ruin any internal rubber, and I think a few days in the chem dip can will do them good.... Also I thought I read a way to measure the floats with a machinist's ruler to determine if they were equal? I haven't touched any of the internals since you set them.

B

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