Should I buy this?

[syren]

I need to tune my carbs but looking for something inexpensive. I know the morgan tuner is a popular choice on this site but will this do the trick? What are the advantages/disadvantages of this type of tuner? Is it accurate?

[reddirtrider]

I need to tune my carbs but looking for something inexpensive. I know the morgan tuner is a popular choice on this site but will this do the trick? What are the advantages/disadvantages of this type of tuner? Is it accurate?

It's only as accuate as the tolerance between the gauges. Personally, I don't like them and think they're a waiste of good money. Sorry if I offended anyone.

[SqDancerLynn1]

I have a set DON'T waste your money.

[rustybronco]

I need to tune my carbs but looking for something inexpensive.

Cheep and works...

http://www.thegsresources.com/_forum/showpost.php?p=496967&postcount=3

It ain't a carbtune, but...

You can pm "bplubin" and get a 2nd opinion on how well it works. we used it on his 77 gs750 last saturday.

[Rover]

Motion Pro

Anyone use a Motion Pro? I have one I bought in 2002 from J.C.Whitney for around $32 bucks.( uses Mercury) I never used it.(long story) Anyway,now
that I'm reviving my GS1000 I plan on using it to sync my carbs after I clean them.

[Steve]

Anyone use a Motion Pro?

Yes, I have used both models that Motion Pro offers. You say yours has mercury. It will be the most accurate, but the mercury reservoir on the one that I used was dangerously flimsy. It had a snap-lock lid on the reservoir that refused to stay closed. Their other model uses a blue fluid that is claimed to be "mercury-free", but there is no clue as to what it is. I have use it, too, and found it to be just as accurate as the mercury.

The dial-type gauges asked about in the original post can also be accurate, but need to be checked every time you use them. Motion Pro includes a nice manifold to enable you to connect all four columns to the same vacuum source so they can be equalized. (This is not necessary with mercury.)

The idea of using a single gauge and a manifold to switch between the carbs seems like a good idea until you try it. If you happen to be very lucky and get it VERY close with a good bench sync, the single gauge will do OK. I have verified this for myself when I visited Lurch12-2000 last year. He had synched his carbs with a single gauge, I checked them with my mercury gauges and they were so close I did not want to adjust them for fear I might get them worse, instead of better. If, however, you are not that close with your bench sync, you will be chasing your own tail trying to sync them with a single gauge. When you have the opportunity to see all four vacuum values at one time, you will be amazed how one small adjustment can affect ALL the readings, not just the two you are trying to balance.

Personally, I would like a Morgan unit when finances allow. The Dollar is strong against the Pound right now, so you can get one for less than $90.
Until the time that I can get one, I will continue to use my SIX-column mercury gauge set.
Yep, paid the extra bucks for it 30 years ago when I had a KZ1300, have never regretted it.

[rustybronco]

The idea of using a single gauge and a manifold to switch between the carbs seems like a good idea until you try it. If you happen to be very lucky and get it VERY close with a good bench sync, the single gauge will do OK. I have verified this for myself when I visited Lurch12-2000 last year. He had synched his carbs with a single gauge, I checked them with my mercury gauges and they were so close I did not want to adjust them for fear I might get them worse, instead of better. If, however, you are not that close with your bench sync, you will be chasing your own tail trying to sync them with a single gauge.

The bench sync I did on those 750 carbs were 8, 8, 8.5, 8.
I have done CV carbs that were off by 2 in. Hg across the bank and didnt spend more than 15 minutes synching them. It just takes practice...

[Dave8338]

The bench sync I did on those 750 carbs were 8, 8, 8.5, 8.
I have done CV carbs that were off by 2 in. Hg across the bank and didnt spend more than 15 minutes synching them. It just takes practice...

FAT skills, ya gotta luv em! Practice and patience goes a looooong way.

[Steve]

The bench sync I did on those 750 carbs were 8, 8, 8.5, 8. ...

Very commendable results, Rusty, but I'd like to clarify something for the newbies that are getting ready to do their first carb sync: IGNORE THE NUMBERS.

What Rusty got with his bike won't necessarily be what you get with your bike. He got 8 to 8.5. If he had done this at an engine speed just a couple hundred rpm higher, the numbers might have been 10 to 10.5. Someone else might get 7.

THE NUMBERS DON'T REALLY MATTER, it's the relative balance between the cylinders that matters.
In fact, many of the mercury gauges don't even have numbers. There are marks about 2 cm apart, but no numbers.

.

[rustybronco]

Steve, you are correct.
The numbers arrived at, on one of the last hondas I did, was around 10.
the numbers are nothing more than a mark on the the dial to compare each carb to the others.

[syren]

Cheep and works...

http://www.thegsresources.com/_forum/showpost.php?p=496967&postcount=3

It ain't a carbtune, but...

You can pm "bplubin" and get a 2nd opinion on how well it works. we used it on his 77 gs750 last saturday.

Rusty, do you know where I can buy one?

[rustybronco]

Rusty, do you know where I can buy one?

I made it out of a vacuum gauge, a 4 gang aquarium valve and the plastic tubing for fish tank usage. I used a brass pipe cap and drilled a hole in the bottom for a metal barbed connector and soldered them together, wrapped the threads on the gauge with teflon tape and screwed the cap on the vacuum gauge.

used vacuum gauge $4.00
4 gang valve and tubing $8-9.00? I bought at a grocery store.
misc parts I had (cap fitting, barbed connector, bolts)