Honda Twins banner
1 - 20 of 67 Posts

· Registered
Joined
·
86 Posts
Discussion Starter · #1 ·
tbpmusic said:
Next, adjust your “air/mixture screws”. Usually, 3/4 turn out from full in will be a good place to start.



Adjust back and forth for maximum rpm, on each carb. If you end up at some extreme, like all the way in or 3 or 4 turns out, you have a problem somewhere in the carb - probably indicates a good cleaning is in order. These carbs must be kept scrupulously clean to work properly.
Once I get the "air/mixture screws" at "3/4 turn out from full in", am I supposed to start the bike and then adjust an air/mixture screw on one carb to get the engine idling as fast as possible (with this adjustment) and then adjust the screw on the other carb to where the engine is idling as fast as possible (even faster than when I adjusted the first carb)? It seems like the bike will be idling pretty fast at this point.

Then, with the engine running, I adjust the "idle screws" to get equal strength pressure pulses from both exhausts. Are the "idle screws" the screws on the "flippers", and is this the point where I adjust the overall idle speed to an acceptable level (12000-15000 rpms)?
 

· Registered
Joined
·
89 Posts
i got a question.......i am having probs out of my right carb. I like the instructions for adjustment you have given i will definately use them.
1. the slide on the right carb doesnt go up and down smoothly like the left one. I have had those things apart and will do so again to make sure they are clean. Is there any way of make a slide move smoothly again? (.i.e some type of material to rub on the surfaces where it contacts the housing).

2. seems to be some spitting of fuel back throught the right carb also. nothing flood like...just minor spitals of fuel. I am sure its all related.
 

· Registered
Joined
·
89 Posts
tbpmusic said:
zx12ryder said:
i got a question.......i am having probs out of my right carb. I like the instructions for adjustment you have given i will definately use them.
1. the slide on the right carb doesnt go up and down smoothly like the left one. I have had those things apart and will do so again to make sure they are clean. Is there any way of make a slide move smoothly again? (.i.e some type of material to rub on the surfaces where it contacts the housing).

2. seems to be some spitting of fuel back throught the right carb also. nothing flood like...just minor spitals of fuel. I am sure its all related.

If they can't pass the straw test well, then they need a good cleaning first of all.
If it still won't slide easily, you're pretty much screwed, find new ones on EBay and clean them.
You probably need a "carb kit" or two, for the float needles.
Ok...think i will take em back off tomorrow and in the mean time search "The Bay" .
 

· Registered
Joined
·
89 Posts
tbpmusic said:
zx12ryder said:
are there any differences between a kit for a '71 from a kit for a '72?

Not really - however don't just assume the new jets they give you in those kits are the ones you need to be running.
I understand that....but i got a box of jets already that i have had for those carbs.

130,135,140,145,and a few bigger sizes....it came with 145's in them.
 

· Premium Member
Joined
·
1,638 Posts
Can someone please add a section on setting float levels? The service manual is kinda weak on that and you need some sort of tool in order to do that. Thanks in advance!
 

· Registered
Joined
·
224 Posts
zx12ryder said:
tbpmusic said:
zx12ryder said:
are there any differences between a kit for a '71 from a kit for a '72?

Not really - however don't just assume the new jets they give you in those kits are the ones you need to be running.
I understand that....but i got a box of jets already that i have had for those carbs.

130,135,140,145,and a few bigger sizes....it came with 145's in them.

Let me know if you want to part with your 135 and 140 jets, I am looking for some!

Thanks!
Henry
 

· Registered
Joined
·
89 Posts
got a prob...My right cylinder isnt doing anything. I know its getting spark because 1. i took the spark plug out and left it hanging on the ignition wire. It sparked ....didnt look like the greatest spark but hey..its a points system. and 2 i had a timing light hooked to the lead going to the right plug and it was picking up the spark pulses. I believe its the right carb. The left exhaust heats up like normal and i cant touch it for long without getting burned but the right exhaust i can leave my hand on it all day. No heat coming out the muffler and the header pipe is just warm.
If you got air, fuel, and volts i am sure some heat should be produced.
The bike will idle but as soon as the RPM's start coming up it starts to die. Timing is correct and the valves are set correctly also. I have alreayd taken the carb apart....cleaned it and put a new carb kit in it. Guess i will be removing it again. Any ideas from anyone? ...
 

· Registered
Joined
·
122 Posts
Have you done a compression test?
 

· Registered
Joined
·
89 Posts
figured out my prob....my pilot jet orifice was blocked.....i cleared it with a .020 guitar string. Never thought to try and clear that thing until me and some other people started talking about guitar string yesterday. They hooked me up with a strand so last night i cleared it and now it idles beautifully. Now however i have to get the off-idle adjustments correct so i will now be working on that. Unfortunately you can't do too much adjusting to these carbs considering installing some Mikunis.........btw...that plug on the bottom of carb...couldnt that be used to set up some type of synching device (i.e. vacuum gage?)
 

· Registered
Joined
·
607 Posts
zx12ryder said:
btw...that plug on the bottom of carb...couldnt that be used to set up some type of synching device (i.e. vacuum gage?)
no that is a bowl drain, however if you had a hollow bolt and some clear tubing it works great for checking float bowl fuel level
 

· Registered
Joined
·
89 Posts
donny662 said:
tbpmusic said:
Next, adjust your “air/mixture screws”. Usually, 3/4 turn out from full in will be a good place to start.



Adjust back and forth for maximum rpm, on each carb. If you end up at some extreme, like all the way in or 3 or 4 turns out, you have a problem somewhere in the carb - probably indicates a good cleaning is in order. These carbs must be kept scrupulously clean to work properly.
Once I get the "air/mixture screws" at "3/4 turn out from full in", am I supposed to start the bike and then adjust an air/mixture screw on one carb to get the engine idling as fast as possible (with this adjustment) and then adjust the screw on the other carb to where the engine is idling as fast as possible (even faster than when I adjusted the first carb)? It seems like the bike will be idling pretty fast at this point.
not that one ...the silver plug in this photo....under the pilot screw.
 
1 - 20 of 67 Posts
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top