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Discussion Starter #161
I hope you did not run it for 10 minutes without a fan on it, you can cook the engine in 10 minutes. It is common for it to take some miles for the rings and valves to seat. Check the valve clearance after some running time.
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LOL I use a big ass fan on my bikes. I dont like c02 poisoning. I actually anticpated a lot of smoke. No smoke at all.
Any time I ride my bikes and put them in the garage, I use this fan to cool them down, I dont like them to heat up the garage a ton.

Check out my mess.
 

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Discussion Starter #163
The rings won't seat without some load on it, put the seat on it and ride it. Excessive idling is actually detrimental to breaking in fresh rings.
Ok good to know, so with all the carb adjusting and syncing I have to do, should I ride it out of tune with the popping and carb backfires or should I chance it by idling it more to get things adjusted.

Im not real fast at doing that stuff.
 

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Popping and backfiring, you have some work to do. This can be caused by three things, first, timing. Check it. Second, a vacuum leak. Third, sticking valves, for this put some Marvel Mystery Oil in the gas. I actually do this on every new engine.
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Discussion Starter #165
Can you help me understand the sticking valve thing? If a valve sticks closed, wouldnt the rocker arm get destroyed by the cam, as something MUST give? If the valve is sticking open, wouldnt the piston hit it?

Very likely a timing issue, Im seeing a lot of arcing in the points as well. They are new. I did check the carb boots for leaks, the only place I didnt check is head gasket.

I will readjust everything now that I got it running and I need to finish putting the bike together before I can ride it.
 

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A sticking valve will hang open for a moment, just long enough for the plug to fire (BTDC) and allow a backfire. If your points are arcing, you have a condenser problem and your points will soon be burnt up.
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Discussion Starter #167
Why does this tank drain so slowly through the petcock? Then it stops so I unplug the cross over line and it f'n gushes out like a fire hydrant.
Going on 20 years making gas messes with this damn bike.

That is all.
 

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Because it is not venting much air through the vent in the gas cap and when you disconnect the crossover line you give it a big hole to vent through.
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Around 90psi is normal if you don't open throttle when doing a compression check.
Your carbs are way out of sync though to get so much higher on the other cylinder ('low' side has throttle plate completely closed, high side is slightly open or you have an air leak)
 
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Discussion Starter #170
I rode the bike today. Im having a few issues that are my fault.
1) there was rust in my tank, the speckle kind. going to rebuild the carbs. I actually had a petcock clog I had to fix from it.
2) Throttle is slow to come down, Idle changes here and there, inconsistent idle. I noticed when I turn sharp the throttle increases alot, so my cable is being pulled, so with that issue the RPM are all over the place, high idle, low idle. Ill have to check routing. With this issue its impossible to tune anything.
3) Right cylinder, mixtured screw turned in causes it to die, but turning it out causes RPM to increase and keep turning it out it has no effect (vaccuum leak?)
4) bike wont go over 5k rpm or 40mph any gear. - Going to recheck timing, check slides, check out advancer with a timing light.

I did clean my tank, but it was 2 years ago. I didnt rinse it out after it set and it formed lots of rust powder. So with that in there, I cant do anything. I am going to buy a better carb kit and rebuild. I use some chinese kit and it sucked. Maybe get new diaphrams? Of course, clean the F out out my tank. I put old sockets in there there with gas, and bang them around, then tap on the tank with a rubber mallet.

I did retest compression. 150 left, 140 right. BUT right side wasnt warmed up, it seemed to quit firing, but then I got it firing again. the air temp coming out of that pipe is cooler than the other.
When I was riding after 30 minutes suddenly I lost all power. Like when I left the petcock off but there was fuel in both lines (clear lines) I limped home and later it was find again. I think I have clogged up carbs. I rode several miles today to get the rings to seat, I just kept it slow. Back fires were minimal. No smoke. Running a heavier dose of mystery oil in the fuel for now.

Im very happy so far. The bike ran a while and didnt lock up. Im looking forward to getting the carbs fixed and getting the power on. Then I can paint etc.

The last time I rode this was 2002. Before that, 1996. these skinny tires are insane, it definitely feels different on the road.
 

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Discussion Starter #172
Disregaurd the throttle cable question, I got it. It was pinching a harness that comes out of the head light between the frame.

I took the carbs apart and cleaned them. Im not getting above 45mph or 6k rpm. My floats were set at 26mm instead of 23mm so I fixed that. I took everything apart on the carbs and cleaned them since I found some rust "sand" in my tank. Put gas in it, put some old sockets of various sizes, shook the hell out of it and dumped it. Did that x3.

May be trying again today.
 

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You have 722A carbs.... OE spec is 26 and I set all mine to 27mm. Follow the Honda FSM and nothing else to set the float level.

Check your points advance mechanism for full travel and smooth operation
 

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Discussion Starter #174
Well I guess I might get overflow tomorrow on the carbs? Common Motors video says 23mm:

It was acting like it was starving for fuell so I figured Id try it. I did have my advancer apart and cleaned it, Ill check it with a timing light tommorrow, ill have to go get one.
I assume what Im looking for is as throttle increases I should see the the marks get out of alignment?

BTW I have the "late style" carbs with inset mixture screw and round floats.
 

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Ah yes the common motors BS. Do not do it that way.

Make sure the slides and bores are clean and smooth. I clean mine with a bit of liquid Bar Keepers Friend then polish with some high temp engine wax made by S100
 

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Discussion Starter #176
I already set my height to 23mm, its actually closer to 24mm though. Im going to try it, why would common motor insist it is 23mm?
My main concern right now is my timing. Why does my timing keep going out of whack? After every time I run the bike its firing late. I had to readjust the points. My backing plate is tight an not moving;. I did check my advancer, it is moving freely. When I move it by hand it does advance.

PS I also used the common motor method for setting timing too.

I UNDRESTAND the manual is the source, but its too advanced for me. there are a lot of little things I dont know. This bike is before my time so I have to use other resources to fill in the blanks and common motor has a monopoly on that.
 

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Common motors turns the carb upside down and uses 23mm. Honda says to tilt the carb until the float tang touches the needle but does not compress it. Measure and bend the tang to adjust. Simple.
When you follow the FSM there is a knowledge base here and other sites to back it up with variables that work, ie my setting the floats to 27mm due to fuel density differences from 1970 to now. Otherwise you are on your own.

Are you also using common motor points? If those they require shimming and messing around with. Nothing like selling something then telling the customer BTW these are defective and need fixing.

Not sure how you can fix the manual being too far advanced or the machine being before your time.
 

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PS I also used the common motor method for setting timing too.

I UNDRESTAND the manual is the source, but its too advanced for me. there are a lot of little things I dont know. This bike is before my time so I have to use other resources to fill in the blanks and common motor has a monopoly on that.
You first problem is using Common motor video's.
You can do it 'easy (and wrong) or do it right.
Download the General Manhual, I think it may be available on here somewhere?
You inveryt carbs then tilt to around 70 degree's so float arm is just touching the shut off valve.
It's better to use 27mm if you use E10 fuel. Common Motor doesn't have a monopoly, it's just people don't want to do any work finding stuff out.
 

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Very first 'hit'
Haven't checked the link yet but you don't need the latest one, something from 1970's will be fine.

This may be better as it's part 1 and part 2
 

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Discussion Starter #180
My points are OEM.

ok Ill start referring to manual and just ask more questions! Im glad I found this sight becuase I wouldnt know enough to question common motor.
With my carbs being set a 23mm, or the floats too high in general, can it cause hydro lock?
 
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