Topic: Carb rebuild questions... *She runs!*

[iron_worker]

No pics at the moment but I suppose I should start up a photobucket account to share a bit with you guys.

So popping on decel is too rich? What about bogging at low RPM? I thought that was an indicator of lean?

This morning I rode 'er to work. Started up pretty nicely considering it was 7C (~40F). However, no one of my overflows is ...well ... overflowin. ha I'll have to get something and tap on it. Otherwise I'll pull the bowl and take a look see.

IW

[iron_worker]

And to add to all this ... I had to ride back home again (spilled coffee on myself ...yay for me...) and I turned the air bleed screws out a full turn ... seems to make it pop worse... but hard to say on a short ride.

I also got the bright idea to try some choke and it seemed to make the popping go away but I wasn't sure if that was because I was cutting it completely off or what. I just thought of it as I was 1/2 a block away from work so I didn't get to play with it much. Need more experimenting time.

I was always going to pull the float bowl quickly at home to see if I could dislodge the crap in the needle ... all bowls are on with the drain facing inwards. Classic rookie mistake.

So here is my theory ... on decel it's going lean which is making it a harder mixture to fire and causing it to misfire completely...sending raw fuel into the exhaust to pop.

Thoughts?

IW

[iron_worker]

So I realize that this is start to be pretty much me talking to myself in my own thread ... but oh well ...

This is some good reading regarding the theory behind popping at decel:

http://www.riderforums.com/mean-streak-performance-upgrades/47507-interesting-read-decel-popping.html

The point of the article is more or less that popping on decel is normal on an engine tuned for performance. To get rid of the popping at decel you would need to have your engine running too rich on acceleration (where the major loads are placed on the engine and more important for engine longevity).

I think I notice the popping a lot more since my left side pipes are more or less completely detached from the baffles due to rust! I really need to get my new exhaust!

IW

[Tews19]

Popping on decel is due to running lean. Did you move it to the 4th notch? I rode mine to work today and I had 3 pops for the 20 plus mile ride. One thing I have noticed is the reaction when giving throttle seems to be slower.
May be due to more gas or running rich? I will have to investigate. Can you put up a video of her running?

[chewbacca5000]

So I realize that this is start to be pretty much me talking to myself in my own thread ... but oh well ...

This is some good reading regarding the theory behind popping at decel:

http://www.riderforums.com/mean-streak-performance-upgrades/47507-interesting-read-decel-popping.html

The point of the article is more or less that popping on decel is normal on an engine tuned for performance. To get rid of the popping at decel you would need to have your engine running too rich on acceleration (where the major loads are placed on the engine and more important for engine longevity).

I think I notice the popping a lot more since my left side pipes are more or less completely detached from the baffles due to rust! I really need to get my new exhaust!

IW

How long before new pipes show up?  Hard to tune if you got big holes. 

[iron_worker]

Yes I know. That is one of my problems at the moment. I ordered from CMSNL.com and they aren't exactly being expedient. My shipping date has been pushed back several times. I'm not exactly happy about spending the $1200 and then not getting anything for almost a month.

I may have to retune when the new pipes are here but I guess deal with that when it happens.

IW

[iron_worker]

Ok guys, here is the update... I took off the afternoon from work "sick" ... (it was slow anyway). lol On the ride home it started running #$%*ty again like I had a plugged idle jet... so I tore into it.

Here is what I accomplished:

-Tore down airbox & carbs
-inspected float level... adjust one slightly
-cleaned out all needle seats (found some crud in the one that was leaking)
-checked the pilot jets ... one of them may have been plugged already?
-moved needle clip from 3rd to 4th from the top
-reassembled everything and took it for a spin

That tear down, inspection, reassembly only took about 2 hours. Then I went for a rip .... bog is pretty much eliminated! She's alive! There is a couple places in the rev range if you jam the throttle wide open it will cough for a split second and then go but I think that is just the nature of running non-cv carbs.

Then I brought her back when she was all warmed up and hooked up my sync gauges. Got the sync pretty much spot on and took it for a rip again.

The throttle response stayed about the same but the low rpm idle smoothed out some. I can idle it down to 1000-1100 now if I want to where I couldn't get it to idle that low reliably before. Nice!

I also fueled her up and washed her.... here are some pics and a vid right after the wash as I parked her.









Hopefully those pics work!

I'm pretty stoked she runs real nice now. Woo!!!!

IW

[Tews19]

Awesome! Congrats

[iron_worker]

So guys I am very pleased with how it runs now for the most part. However, now on the highway the clutch seems to be slipping in 4th and 5th at WOT. Also it wouldn't rev out in 5th so I'm not sure what to chase now:

-First I think I will adjust my clutch as per the manual
-I know I have some voltage drop to my coils so I will try to trace that
-I could do a plug chop at WOT to see what is going on but I don't think the mixture is far off
-At some point I will get some genuine Honda points and get the timing/dwell dialed in exactly (it's really close so I don't think it's that either)

I suppose I could also do a compression test just to see?

Any other thoughts?

Thanks,

IW

[chewbacca5000]

Way to go IW!  Bike sounds good.  I wouldn't really do much else except see if you can weld up that side left exhaust pipe.  Having one cylinder with different back pressure does make a difference.  You can take a soda can or other aluminum and a hose clamp as a temporary patch.  Actually works pretty.  Bike is looking good keep us updated!

[Tews19]

Pm me. I have a lens you can have for your rear turn signal. I would adjust the clutch. Make sure timing is spot on. Then work on getting the exhaust welded. Maybe even do that first if you have the means to it. May help the bike. Other then that it sounds really good

[iron_worker]

My new reproduction 4 into 4 exhaust has shipped from CMSNL.com recently. I will put putting it on ASAP. I'm pretty excited to have a bike that will run much like they did back in their era.

I may also have a lens .... but I may PM you since I can't seem to find it. ha

And thanks for the kind words guys.

IW

[Tews19]

My new reproduction 4 into 4 exhaust has shipped from CMSNL.com recently. I will put putting it on ASAP. I'm pretty excited to have a bike that will run much like they did back in their era.

I may also have a lens .... but I may PM you since I can't seem to find it. ha

And thanks for the kind words guys.

IW

PICS OF NEW PIPES OR IT DIDN"T HAPPEN!!!!!

[iron_worker]

I will post pics when I get the dang things! Apparently shipping from the Netherlands take some time. lol

IW

[lucky]

So guys I am very pleased with how it runs now for the most part. However, now on the highway the clutch seems to be slipping in 4th and 5th at WOT. Also it wouldn't rev out in 5th so I'm not sure what to chase now:

-First I think I will adjust my clutch as per the manual
-I know I have some voltage drop to my coils so I will try to trace that
-I could do a plug chop at WOT to see what is going on but I don't think the mixture is far off
-At some point I will get some genuine Honda points and get the timing/dwell dialed in exactly (it's really close so I don't think it's that either)

I suppose I could also do a compression test just to see?

Any other thoughts?

Thanks,

IW

If the clutch is slipping in 4th or 5th gear you will need to get some new clutch plates. If you let them keep slipping you will ruin or warp the metal plates.
Common problem on bikes that sat for a long time.
Sometimes it can be the type of oil. Do not use car oil that has "friction modifiers".


Good move on the needle clip change.
What size is the idle jet now?

[iron_worker]

Thanks Lucky. I don't think my oil has friction modifiers ... just plain old 10w40 but I could check. The bike hasn't been sitting for a long time. It's been running for the last 10-15years ... just not very well. This is probably the first time it's run reasonably close to how it should run since I've seen the bike. My theory is the clutch may have some accelerated wear on it from having to feather the clutch out a lot since it ran horrendously at low RPM... for the last 10+ years. lol

My settings are:
40 pilot
110 main
4th position on the needle clip (from the top)
1 turn out on the idle mixture screws
stock air box / stock type filter element
stock 4 into 4 - in rough shape/leaky

My latest and greatest problem now is that the electric start won't work. ha! I was dicking around trying to measure voltage drop to my coils last night and pulled the headlight out (headlight fuse doesn't turn off the headlight?) and I may have bumped something around. My electrical is in bad shape so once the exhaust is on I think that's probably the next project. A complete harness isn't super expensive so I may just go for a new one and be done with it.

I kind of wanted to build a custom harness (for fun and learning) but I think that would have my bike down too long. That's sort of a winter project I think.

Things I still need/need to do:
-either pull my harness and clean all connections/check integrity of wire or replace
-remove coils and clean all connections/grounds
-replace carb to airbox rubbers
-replace airbox seal (between halves)
-get proper wingnuts for airbox
-K&N air filter maybe?
-New tail light lens cover 
-Get genuine Honda points and dial them in 100%

There are more things but those are probably highest on my priority list for now.

IW

[iron_worker]

Well I was curious about my electric start not working so I went out to check it out at lunch. The bike fired right up using the electric start ... hmmm. I'm thinking my battery may be on the way out. I noticed last night that my battery voltage was dropping pretty quickly even with my headlight unplugged and my points unplugged.

So I guess that's one more thing to look into and replace if necessary. Easier to fix than a fault in the electrical somewhere though so that's good.

IW

[chewbacca5000]

Well I was curious about my electric start not working so I went out to check it out at lunch. The bike fired right up using the electric start ... hmmm. I'm thinking my battery may be on the way out. I noticed last night that my battery voltage was dropping pretty quickly even with my headlight unplugged and my points unplugged.

So I guess that's one more thing to look into and replace if necessary. Easier to fix than a fault in the electrical somewhere though so that's good.

IW

Simple corrosion on the push button can do that too.  At least on my 73.

[iron_worker]

Yes that's possible as well. Although it's never done it until now and it was right after I was screwing around with the electrical ... so likely it was my fault. ha

IW

[lucky]

RULE#1

You cannot diagnose any electrical problem until you have a SOLID source of 12 volts.
THE BATTERY.

Check the battery voltage when the bike is off and after it was ridden.
It should read about 13.4 volts. NOT running. That is because each battery cel is 2.2-2.6 volts or more. 2.2x 6 cells=13.2 volts. That is a good battery.

Don't make me post a video.