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Discussion Starter · #1 ·
My bike upon first start will idle around 1500 for around 1 minute before it dies.
It will stay running with throttle, so I ride anyway.
When riding it dies when I push in the clutch in first gear to come to a stop.
While riding it doesn't seem to have any problem but this is my first bike and I'm not a mechanic so it's possible there's something I'm missing but it has good power and doesn't smoke, pop or seem to miss at all.
Back from the ride I try to idle but it won't so I hold the throttle wondering what's up....I smell gas strong enough to make me wonder if the fuel mix is set properly.

I understand how to seat a screw and how to turn it back out 1-1/4 turns and go from there.
(this is a twin so I'm assuming I will have to do both sides?)
I'm encountering the problem that it won't idle to a warm state and give me a base idle to work with.
In order to for it to be running I have open the throttle and hold it.

Just wondering if anyone has a trick or more knowledge that might help. I've read on this forum for about an hour now but they all say the same thing.
Warm up the bike, seat the screws, turn out 1-1/4, slow down and hunt the sweet spot.
If I missed one with information on how to do this with a bike that won't idle please point me in the right direction.
Also possible I might need to have a bit more patience?
Just that something tells me I don't really want to be twisting these screws back and forth and back and forth and back and for...
Thanks !

P.S. This bike is in running condition but it's old and was taken care of well enough to still be ridden but it might very well have some deeper issues. All intuitions welcome.
 

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It would help to know what rpm you can keep it running at with the throttle.

If it won't idle at all you're not going to fix it by adjusting the mixture screws. I suspect that you already know there is also an idle speed adjustment screw. It's possible that this has backed off to where the setting is too low to keep it running.

It's also possible that the idle circuits are plugged so it has to run on the slow jets which could cause your symptoms as could a vacuum leak.

Welcome to the group.

We'd appreciate a post in the member introductions section to let us know a bit about yourself and your bike(s). And we really like pictures! :p
 

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Discussion Starter · #3 ·
I can keep it running at 1500 as long as I hold the throttle open just a bit.

I was aware there was an idle adjustment screw but I'm not sure where it is. I ordered a service repair manual but it won't be here for a couple days. In the meantime I'm googling.

Since my last post I rode around the block and this is what I encountered:
had to gear down to first to make it up a hill, pretty sure I was holding the throttle open quite a bit just to make it up, after I topped all was well
got to the stop sign, it died
started back up rode on a bit then another stop sign and it died again, took about 10 kicks to get it going again
(for some reason the brand new battery is dead so I couldn't push start, usually starts very easy with push button or 2 kicks)
made it home okay but wasn't interested in taking it around a second time
after I pulled in I could grab my left exhaust and hold on till tomorrow, stone cold - but plenty of air flow out the back
(pictures below, previous owner had replaced left side)

Any problems detected from pictures below please do share.

I've decided to take it into a shop for it obviously could just use a check up but I would love to hear from others who have encountered this or who have a real knack when it comes to explaining the why for's

Thanks again!
 

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Sensei
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Just from the pix, it APPEARS that the idle MIXTURE screws (the ones nearest the aircleaners and bowl) are set very differently.....The left side SEEMS to be closed much more than the right side....These are the screws that should be gently seated and backed out to 1 & 1/4 turns open (as a starting point)....
Idle (speed) screws are the longer brass ones centered on the slide columns.....
Then you have to adjust/sync the carbs for a 1200RPM idle.....
 

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Discussion Starter · #6 ·
Since the mismatch pipe will be trouble making I'll replace the other as well.
Any explanation (long or short) or direction to text on why it's trouble will be helpful for future reference.
I'm sure optimum performance calls for matching pipes but I guess what I'm looking for is problems the mismatch causes and why.
If you have time to babysit me that is... ;)

I'll try adjusting the left side mixture but I will say that the angle from which I took each picture makes the left look different.
The larger (fuel) screw on the left side is backed out somewhat close to the same distance as the right when looking from above.
I'm assuming however that there's a minute click precision that can't be seen with the naked eye and I agree the left looks a bit farther out.
I've attached a couple pictures with better angle.

I considered the other longer brass piece as the idle adjustment but it doesn't have "screw" characteristics and I was looking for a screw.

Much appreciated.
 

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Discussion Starter · #7 ·
A few videos, none of which I can get the bike started now.
When I brought it home it would idle for about a minute and has progressed to no start in two weeks without anything from me but a new battery, some new plugs and gas.
At that point I could push start with minimal throttle and it purred for about a minute at 1200-2000 then it would die. After that in order to ride I had to keep a bit of throttle on it to keep it going at standstill.


a few details ---

pre fuel/air adjustment ---

after fuel/air adjustment
---

When I first backed out the fuel/air screws I accidentally went 1-1/2, no luck, then went on to 2 turns, no luck
I back tracked and tried again to 1-1/4, no luck, then on to 1-1/2, no luck
Still better than the flat refusal to start I got before I did anything, which I didn't capture on the pre adjustment video.

The first two videos are outside, the third inside, it started to rain again it's been raining for many days straight.
 

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It LOOKS like you have an inline fuel filter in the first picture you posted. Have you tried replacing those to eliminate the possibility that they are clogged?

Also, you have a lot of tarnish around the carbs, which may indicate a fuel leak at some point. Are the undersides of the float bowls (bottom of the carbs) ever wet with gas?

Have you tried taking the carbs off and cleaning everything with carb cleaner? Not sure how comfortable you are with that, but it's really not too hard.

PM with an email address if you need a PDF of the shop manual.
 

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Discussion Starter · #10 ·
I've studied the fuel filters by staring at them repeatedly.
Honestly I've spent a fair amount of time just sitting on the floor by the bike and staring at all the parts and another fair amount of time researching what I'm looking at.
A PDF of the manual would be great but I already ordered one so I'll save you the trouble since it should be here tomorrow.

I'm not sure what a new filter would look like but these filters look "weak" if that makes any sense, with some fray around the bottom.
I've watched videos and read up on removing the gas tank to get rid of the rust and figured when I do that and remove the petcock that I could replace the filters while I'm at it. Perhaps I shouldn't wait til then.

I haven't yet noticed any gas seepage anywhere but I didn't know to check the underside of the float bowls, I'll inspect further to be sure and try to get a picture.

As for cleaning the carbs I'm comfortable doing most anything as long as I have detailed instructions and a backup body to question.
(I should definitely wait on the manual :!: )
For instance, I've been looking for the idle screw...separately from the fuel/air mixture screws and now realize from the picture you sent that the fuel mixture screw and the idle adjustment screw are one in the same.
I thought there were three because I've read about adjusting fuel/air mixture screws and also about adjusting the idle screw but haven't seen them described as the same thing. (Pictures help tremendously but I never found a diagram like the one you attached). Because I have no knowledge I tend to take things very literally. It's like trying to perform heart surgery with only a general knowledge of where the heart is and the result you DON'T want to achieve. But that's okay, I will learn.

Again, thanks!

P.S. - So the battery not keeping charge is common and normal? If so I will pick up a charger tomorrow.
 

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Discussion Starter · #11 ·
Finally got started but still no idle
Before the video begins I set both fuel/air to 1-1/4, started up on the 2nd kick, let it run a bit to warm up and tried to adjust the fuel screw to get an idle, it would not. The left exhaust doesn't even hint at getting warm, the right side too hot to touch.

failed idle adjustment


My brain has overdosed on too many helpings of carbs and I didn't even eat the bread.
 

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Hi
The 175's and 200's need fairly hi revs to charge so is you're puttering around or in the shop it's easy to drain the battery and the bike won't start or run well with a weak battery
The in line filters are a cheap / disposable way to keep the fuel clean the plastic should be clear and the petrol slightly purple ( yours look yellow so I'd replace them they should only be a couple of dollars )

The cold pipe is the one to worry about it means that you're only running on one cylinder ( the hot one)
 

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brassInpocket said:
For instance, I've been looking for the idle screw...separately from the fuel/air mixture screws and now realize from the picture you sent that the fuel mixture screw and the idle adjustment screw are one in the same.
NO!...THEY ARE NOT!.....The "AIR SCREW" (#2) is for the FUEL/AIR mixture @ IDLE (only)...(While you adjust it {Within the specified range} to achieve the highest idle, that in reality sets it at the optimum mixture ratio),.... The screw marked "STOP SCREW" (#1) is for setting the IDLE SPEED

Phone me to discuss if need be.....540-525-5199.... Steve
 

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Discussion Starter · #14 ·
Thanks Steve but yes, I get it....apologies, possibly I didn't say it right.

At first I thought the larger screw was fuel mix, the smaller screw was air mix and I was still looking for a third screw as the idle screw.
After the picture I realized the larger screw (#1) IS the idle screw [what I thought was for fuel mix] and the smaller one (#2) is the fuel/air mix.

What made that so difficult to grasp is that in all the video's/blogs/forums I researched the #1 screw was never called a stop screw or an idle screw.
They were simply explained as mixture screws, one on the fuel side and one on the air side and instructions on how to adjust them.
Someone familiar with the workings of a carb would have probably understood but as a beginner who knows absolutely nothing, diagrams and proper part names are a must.
As soon as I saw the manual diagram, it clicked.

Thanks again for lookin' out for me and please let me know if I'm still misunderstanding. :)
 

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Discussion Starter · #16 ·
Here is a look at the plugs.
[ 2 weeks / 10 short rides old.]
Left side is the cylinder not running.
I kept the left plug out to check for spark but I can't get it to start again. Went out and got the battery tender, on charge, try again tomorrow.
 

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Instead of removing that screw take the nut off that's directly behind your finger in the last photo
So that the carb and the manifold ( that's the black bit between the carb and the engine )
come off together

Also get a big plastic bin and put EVERYTHING that you take off the bike goes in the bin so that it all stays together
 
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