1st gen Carb sync.

[timgray]

I have read tons of threads on carb syncing but I cant find any of the threads that people have been talking about that are carbtune howto's or guides.

 

Anyone have the links on how to use the carbtune or sync carbs on a 1st gen?

[Condor]

Sorry for the non-replies Tim. It's just that the subject has been hashed and rehashed over and over on this board. There is a how-to for the second generation in the tech section for the 2ndGens and it can be applied to the 1stGen's as well, and there's also a good discription on the sequence in the manuals section for the 1stGens. For generic what it does, and how-to instructions, there's good reading on http://www.carbtune.com/. If you do a search on this board for all threads on carb sync's, and you read them all, you should be an expert by the time you're through....

[timgray]

thanks, I've tried the search, and all I get are threads asking about it or diagnosing it but no threads (from the search function) that say how-to. I'll take a look where you pointed me at and start there.

[Guest Fly-N-Lo]

Hi Tim, Try this link out: http://www.venturerider.org/forum/showthread.php?t=495 Should be what you are looking for. When you look in the vrtech section of the site, you may have to expand the date range back to the "beginning" to show any threads. Most are posted over the default "last week" setting. Good luck. It really is just a 15 minute job.

[Condor]

Hi Tim, Try this link out: http://www.venturerider.org/forum/showthread.php?t=495 Should be what you are looking for. When you look in the vrtech section of the site, you may have to expand the date range back to the "beginning" to show any threads. Most are posted over the default "last week" setting. Good luck. It really is just a 15 minute job.

 

Try here. http://www.venturerider.org/forum/showthread.php?t=258

[Guest Fly-N-Lo]

Better yet there Condor...Had Don's in mind but came to the 1st Gen article first. His is a much better explanation. Same principle different pictures...right? Either way, easy job.

[Condor]

Better yet there Condor...Had Don's in mind but came to the 1st Gen article first. His is a much better explanation. Same principle different pictures...right? Either way, easy job.

 

Missed that one. I guess that takes care of the questions....

[keikat02]

Please forgive my ignorance; however, I just want to make sure I understand.

 

In my Yamaha Service Manual, it states to set carburetors 1 and 2 using set screw "A". However, from what you are stating, this is wrong and should be done with set screw "C"? Correct?

 

Then, the manual states to set carburetors 3 & 4 with set screw "B" which appears to be what you are stating. Correct?

 

Finally, the manual states to set the left side to the right side by using set screw "C". However, from what you are stating, this is wrong and should be done with set screw "A". Correct?

 

Allen Squyres

Dallas, Texas

[Freebird]

Allen,

If you are going by my write up in the second gen section, the mistake referred to in the manual only applies to the second gen. As far as I know, the procedure and screws shown in the first gen manual are correct.

[Squidley]

I have read tons of threads on carb syncing but I cant find any of the threads that people have been talking about that are carbtune howto's or guides.

 

Anyone have the links on how to use the carbtune or sync carbs on a 1st gen?

 

 

Tim,

I'm north of Detroit, if you want to shoot over I have a carbtune and would be glad to sync the bike for you and show you how it's done.

[timgray]

Thanks a bunch for the offer! That would make it easier to understand when I get my own carbtune.

 

I will be in touch!

 

Thanks everyone for the info! I have been given a ton of reading now that covers every aspect of this.

[Dano]

I like the end of the directions: "Go for a ride"

[timgray]

Ok I just built a home gauge. used the tubing and followed all directions. heated up the bike, hooked it up to carb 1 and 2 restarted the bike and watched as all the ATF in the tube get sucked into Carb #2 faster than I can kill the engine. it sucked it in incredibly fast. Home made carbsync gauge is all done. The screw for adjusting #1 is bottomed out, if I loosen it the bike stops idling, I have to return it to the bottomed out position for the bike to run..

 

I took apart the air box and looked down into the carbs. at idle the pistons do not dance. they only dance when I reve the engine.

 

So any ideas? I'm guessing I need to buy the real gauge from England (I'm guessing I cant suck the little metal rods int othe carbs.) because my carbs are so far out of sync it's not funny.

[Squidley]

Tim,

My # is in my profile, give me a call and maybe we can get your bike tuned this weekend.

[Neil86]

Tim...

the problem with using light fluids (oil, water, etc) instead of mercury is you need a very tall manometer to prevent liquid ingestion. It sounds like your throttle stop screw for idle speed (which operates #2 butterfly, and everything is linkaged to it) is backed off too far, so #2 butterfly is closed and its vacuum is too high. Try bringing up the idle speed with the stop screw first, then synching, then bringing the speed back down, and resynching as needed. It sounds like you are only idling with #1,3,4 cylinders.

[timgray]

Squidley thanks for the offer! Out of town this weekend with work but I'll call you and see if I can make it over one of these weekends. I have never taken the bike on a 200+ mile ride so I'm kind of leery of going that far without going through everything beforehand.. maybe I can find a friend that will ride with me on over.

 

And for everyone offering the loan of a carbsync.. Thanks you very much. You guys are a great example of how bikers stick together. If I cant get over to Squidleys place to get it synched I'll be taking up an offer of the loan until I can get my own tool.

 

you guys rock!

[timgray]

A buddy of mine this weekend made me sync my carbs with his hotrod single carb vac gauge.

 

I'll tell you guys, this is far easier than you guys make it out to be, even with a single gauge.

 

I hooked up the gauge to carb#2, it was bouncing all over, so he handed me a set of vice grips and said, "clip this to the hose. pinch it off." I did and then adjusted the screw on the vice grips until I had a little bounce in the needle. I then used the cruise to set the rpm to 2500 and took a reading. removed the hose, plugged carb2, unpluggged carb 1 and set it to be close to what 2 read. swapped back and forth until they were the same as far as I could tell. did the same for the rest.

 

After getting #4 done I went back and set the idle as the previous owner had it set to not idle. then readjusted (very little) the 3 carbs to #2 once again.

 

That was incredibly easy and you do not need the 4 gauge setup or even a 2 gauge setup. the single $19.99 gauge from the local auto store works great. It's harder to get all 3 side plastic pieces off than it is to tune these carbs up.

[Neil86]

You probably got them a lot closer than they were...nothing beats being able to observe all 4 intake vacuum readings at the same time.....due to the mechanical linkage inside a guage consistency even using one gauge is a problem. Did you find extremely high vacuum on one carb when you started?

[timgray]

Yup Carb #2 was off the scale at idle I had 15 inches of water vac at idle and it was 6 inches of vac higher than all other carbs at 2500-3000 rpm. So I cranked up the rpm and then adjusted #1 to match. The Idle screw was backed all the way out and #1 adjust screw was bottomed out against the spring when I started. The Previous owner started twisting screws for fun and stopped when he had it all messed up.

 

#3 and #4 were very close to each other but were far off from #2 as well.

[Squidley]

Tim,

Your still more than welcome to come over and we can double check all of them with the carbtune.