$140 Carbtune Pro vs. $40 eBay Special Carburetor Synchronizer Gauges

The cheap gauges are probably good enough. The Carbtune is better. This experiment isn't that thorough, but I wanted to know if I was in the ballpark with the cheap gauges. I was.

[@email4664]

You are not experienced enough to know the difference between quality and lack of. Stick with your cheap tools, and poor quality adjustments. Real mechanics can just fix it after you fuck it up

[@matttriestodothings]

hahahahaha

[@rticDriver]

Great videos by the way enjoyed watching them.

[@matttriestodothings]

Thanks man, I appreciate it.

[@eivindlukasmoenfasting1602]

Nice video Matt, my Honda VF500F carbs are on their way from the US.Ordered me some cheap carb synch gauges that hopefully will work out ok.

[@matttriestodothings]

Awesome--I hope it all works out easily for you, and you're on the road soon!

[@LanciaD50]

thanks for the video! I calibrted my cheap gauges on the zero, but i never managed to get the bike smooth down until i did it by helping me with my ear to have a purring idle. I'll probably make it with carbtune

[@matttriestodothings]

Thanks Dan. Some bikes seem a lot more sensitive to the synchronization than others in my experience. This Bandit wants to be damn near perfect whereas my SV650 is like, ehhhh... close enough, and it runs fine.

[@giostisskylas]

I've tried everything. The hose method, the cheap synchronous clocks. Even high-quality synchronous clocks. I've spent more money on the "cheap solutions" than a Carbtune Pro cost (around €95 here in Europe). Do yourself a favor and don't even try the cheap solutions. It's a hassle and you don't save any money in the end. Only Carbtune, nothing else. The elegance and precision lies in the ingenious simplicity of the Carbtune.

[@matttriestodothings]

I'm inclined to agree that just going straight carbtune is the best and easiest idea for a tool you'll likely have for the rest of your life.

[@zook_750]

Hope you're well Matt. Thanks for this video; I'm just about to buy a Carbtune and needed to see a comparison test with the old skool style. Have you seen the digital synchronizers you can buy these day?. They're not cheap but super accurate; I believe the Digi-Sync brand is made in the U.S.

[@matttriestodothings]

No, I have not seen them. Coincidently I used my Carbtune for the first time this year a few days ago. That digisync seems like a pretty neat tool. I'll have to watch a review or two to see if it can deliver on what it claims to do. More importantly, the company's logo is awesome. Good octopus.

[@billsmart2532]

Agree with your conclusion. However competitive track riders need to tune their bikes to the highest standard. I found the mercury tuning stick to have a level of accuracy above my gauges even after adjustment.

[@AznCracker13]

Ayy go blue I have the same hat. Wasn't sure of the difference between the two but this video convinced me to get the Carbtune. My thoughts is that it'll cost as much as taking it to the mechanic so might as well do it right. Also the time to calibrate it every time will probably cost more in the long run (time == money).

[@matttriestodothings]

Go Blue! If the extra $100 for the Carbtune isn't doing to bankrupt you, it's probably the right choice. It's a neat tool that's more accurate and saves time you'll have for the rest of your life. However, the cheaper gauges *can* work just fine--unlike some people's claims that they're pure trash.

[@matttriestodothings]

Do you still have the poof ball on your hat?! A friend's dog ate mine off, haha

[@AICD1999]

as you know, each carb will be physically different as well and synch can be a bit dynamic meaning not static. Always hang those gauges to minimize interference.

[@matttriestodothings]

Ah, you know.. this is true. I've hung the gauges every time in the past, but I wanted to go for a better camera angle this time. But you're right, they should be vertical to minimize interference.

[@JBK647]

What sort of interference?

[@areshuan]

Great review . Thank you

[@matttriestodothings]

Absolutely. Thanks areshuan

[@kwakgreen]

This is the reason why I ditched these exact same gauges, because of the inaccuracy, I could never get the bike to run smoothly, until I bought the Carbtune. Now it just purrs on idle and runs better.

[@matttriestodothings]

This set doesn't seem too bad but requires that you go through and calibrate them for peace of mind. The CarbTune is certainly the easier of the two by far, and I'm glad I bought it. I think the standard vac-gauges can work decently though.

[@kwakgreen]

@@matttriestodothings I get what your saying Matt, even after calibration and altering the set screws on the carbs the gauges never gave an accurate reading.

[@keithbainbridge4964]

Hi im an old school (60 yrs) bikeing & i was always taught that any style of synchronising that whatever you are using that the gagues & tubes should not be touching any part of the bike/car as the vibrations can give a false reading !! Just as an aside if you have to use vacuum adaptors with the carbtune pro be aware that the plastic adaptors can brake in time but new carbtune pro now come with brass adaptors so problem solved 👌👍

[@matttriestodothings]

Great--so the little restrictors I bought with my $140 carbtune are another liability in my life, hah. That's good advice about the gauges and tubes not touching anything vibrating. Any vibration in them is going to travel through the device and somehow affect the needle. I imagine the degree to which it is affected goes from "negligible" to "significant". So minimizing that however possible would be good practice. Thanks for the advice Keith.

[@keithbainbridge4964]

Mat you miss understood my point about the adaptors, i was not talking about restrictors my friend, i was talking about the fact that not all bikes/ cars vacuum take off points are a push fit with the supplied tubes some are 5mm thread on carbs & some are 6mm thread so therefor you need to thread in the correct adaptor before connecting the gauge tubes it is these adaptors that come with carbtune are made of plastic & after a short time break, if you contact Morgan carbtune they have now replaced the plastic adaptors with 4 short 5mm ones & 4 long 6mm ones, as for gagues & tubes i made a free standing metal holder to take either the round dial gagues & the carbtune pro which must be kept upright to get spot on readings, oh & my stand is weighted on base which goes under the bike or car & also holds a 1liter fuel tank & supply tube all of which are adaptable for height & width just slide & thumb screw fittings, i hope this is of some help to you buddy, happy bikeing & ride safe 👍👍👌👌😂😂😂

[@michaelfirth1075]

Great video 😊

[@matttriestodothings]

Thanks Michael.

[@UnCivilEngineerIRL]

Awesome, we'll worthwhile doing the comparison dude.

[@matttriestodothings]

I probably should have spent more time showing the values of the readings of the vac-gauges vs the Carbtune at the same engine RPM. But I think this shows that the cheapies can at least be in the ballpark and better than an eye-balling bench sync.

[@UnCivilEngineerIRL]

@@matttriestodothings was wondering if the budget ones were any good before, glad to hear they are at least reasonable. Thanks bud.

[@yveslegrand9826]

Actually it is better and easier to put a set of 3 differential pressure gauge and just adjust the carbs so that you get 0 difference between 1/2 3/3 3/4. Each gauge is adjusted by the matching adjustment screw. Simpler, easier faster. However the synchronization is never perfect and between full idle and full open throttle the pressure balance is changing a bit. It should not be a lot except you have something bad on a carb (membrane, slide, spring...) and I would prefer to have the "best" synchronization with just a little throttle. Perfect idle is not really useful, but perfect rev up is a must.

[@matttriestodothings]

I can see how pressure differential gauges could make it easier--I've just never come across one before. Some bikes seem rather sensitive to sync while others I've touched seem to have a much wider range of tolerance. Interesting point about choosing the Rev range where you'd want best sync as well. I hadn't thought of that.

[@yveslegrand9826]

I am using very (too!) sensitive Magnelic clean room HVAC gauges. They are 5mm Water level FULL SCALE. At iddle speed, the needle are vibrating so badly that they are barely visible when the carbs are perfectly balanced...and blocked on one side otherwise. The good thing is they are rated for 15PSI over pressure each side so it's no way you can damage them with vacuum.

[@ericespinosa7656]

Dam uk about it I can see

[@ralphparker]

If you don't have a budget get the best. Carbtune Pro is a great tool and not too expensive. But I've got a motor (outboard) the carbs [ 2006 Honda ] are messed up and I want to get them in a good place. The $40 would seem to do that for me. If I was racing a motorcycle, I would tune it up with the $140 device. For me, it may be do it once and done. or part of a periodic maintenance when idle RPM's are off the 1000 RPM target. If the Idle gets to low, it dies when going from neutral to into gear. If you know what pressure you are working with, calibrate it there. Thanks for the video.

[@matttriestodothings]

Yep. I could justify the Carbtune Pro to myself because I use it several times a year. That's a tough sell if you're just using it once after rebuilding carburetors and don't intend on having to use it again. My experience says that cheap gauges can be 'good enough'; however, they come with the increased risk that they're likely not calibrated correctly, so you'll want to find some way to do so. Thanks Ralph--cheers.

[@ralphparker]

@@matttriestodothings How I calibrated my $40 set is I bought vinyl tubing and tees and hooked all the gauges to a mityvac vacuum pump. I pulled 10 inches of vacuum to one and set all the other gauges to the exact same value or at least as close as I could. I think you will want to calibrate the gauges everytime you use the device. I think it would be easier to use the Carbtune Pro to get those precise numbers as reading the values seems to be easier as I watched videos of the carbs being synched. If you know what value your gauges settle at during the process, You could pull a vacuum to that value and make the other gauges match at that vacuum. 10 inches turned out to be a good value for my experience since the values settled in the 7 to 8 range. Cheers!

[@saltyshellback]

I bought a set of those cheap gages and they were absolute garbage. I would set them all to zero and a few minutes later, two of the needles would drift again. Also, I would swap the location of the hoses just to see if the readings were the same, and they weren't. For example, I would get 2 and 3 set to the same pressure and then swap the gages and they would read different pressures from before. I think it is the luck of the draw whether you can get decent gages in the set you buy. I think I'm just going to save myself a lot of time and headaches and just get the Carbtune.

[@matttriestodothings]

Ah, that sucks. I agree, it's definitely a gamble buying the cheaper gauges. Looks like mine are actually pretty decent but your story is one I've heard before. It just kinda sucks how expensive the Morgan is! It's a nice tool to have though.

[@ambrechambers7094]

Check your pilot jets! It's taking to long to get back to idle. They will never be perfect synced! Sounds good!

[@matttriestodothings]

Pilots were fine--had them out probably 10 times over the years I owned the bike. If there was a blockage anywhere, it was likely within the pilot circuit though that lead to the progression holes would be my guess. There's really no way I know of to test for solid debris blockage in those areas. You can shoot fluid through to see that it drips through them, but that's about as good as I can think of.

[@Mad8vCycles]

have you seen the diy "oil and hose" setups?

[@matttriestodothings]

Like the homemade manometers? The one I quite liked was done by this guy "Dustin Rogers". I liked his setup because there was no way it was going to suck any of the liquid into the engine. He had a video showing it for a throttle body sync on a vstrom here: kzbin.info/www/bejne/fYHMn6Rml9SEqas I haven't made one myself though.

[@FranciscoGalicia]

Thanks. Do you need a. Air -vacuum regulator or they go directly to every carb. ?

[@matttriestodothings]

They go directly to each carb. There's a little restrictor on each like to try to steady out the bouncing needles.

[@FranciscoGalicia]

Thanks for your reply. Do you recommend them?

[@matttriestodothings]

@@FranciscoGalicia The tough part about recommending the ebay vacuum gauges is that it's a bit of a crapshoot. I trust mine after doing this experiment to get me close enough for sure. But unless you go through with trying to establish a baseline, you may be working with false information. They've worked for me though.

[@randypullman1155]

The cheap gauges as you are shot by now. The gauge with liquid also a one and done. I would have tried a calibration test on the carbtune to see if in fact they were accurate.

[@matttriestodothings]

What do you mean by shot? I'm not sure a static pressure calibration test would work per their description of how it operates (the bouncing sticks). The only way I could think to test that would be from a 4-way tee off of a running engine.

[@JBK647]

Please revise this so it's understandable.

[@rticDriver]

Turn air screws out about 3 turns on gsf600 brings down revs quicker don't go by Manual, i made that mistake.And it depends on how far above sea level we are based in UK

[@matttriestodothings]

3 was too rich and sluggish for me. I couldn't get it to run correctly there. I think I ended up settling at 2 turns on the A/F mix screws and 2 shims on the needles.

[@rm25088]

I was having a hell of a time with these cheap pieces of crap. Buying a real sync tool this time.