Jump to content

which guages for carb balancing?


awol ali
 Share

Recommended Posts

hello folks, i have a 2005 dalesman outfit (lol to you over the pond they called 'em tourists)

 

just want to ask which gauges you use to balance the carbs, as i'm bout to get a twin max and want to know how good it is or is there a better option.

 

cheers ali

Link to comment
Share on other sites

hello folks, i have a 2005 dalesman outfit (lol to you over the pond they called 'em tourists)

 

just want to ask which gauges you use to balance the carbs, as i'm bout to get a twin max and want to know how good it is or is there a better option.

 

cheers ali

 

I think it really comes down to cost. I have never used a TwinMax, but I have seen one in use and it compares in accuracy to the manometre. The manometre works very well for me and will cost you a fraction of what a TwinMax does.

 

http://www.uralhowto.org/index.php/site/co...chronizer_tool/

 

http://www.airheads.org/content/view/183/98/

 

Berger

Link to comment
Share on other sites

Make one it will work as well as anything, and they cost alot less. Rick

 

Second that! The Twinmax is a nice tool but if you are only using it to tune your own Ural, its overkill. Carb sync can be accomplished with nothing more than some vinyl tubing and a yard stick(meter stick?).

Link to comment
Share on other sites

An MG shop manual I have has a carb balancing procedure that uses a piece of heater hose held to the ear, you listen to the whoosh of the air flowing through the carb throats and adjust the throttles until they sound the same.

 

Dave

Link to comment
Share on other sites

I read and assembled one of those homemade sets and it works like a charm... probably spent less than $3. highly recommended it. ride and warm up your bike, get a couple of box fans to cool the motor, hook up the tubes to the vacuum plugs and balance away....

Link to comment
Share on other sites

I personally think your factory installed speedometer is the best (and cheapest, and easiest) gauge for syncing carbs. It's a no-nonsense, real-world, performance based method with empirical results that should over rule all other methods for getting proper carb sync.

 

It just makes sense to me that you can't get no better sync-ed as long both sides are running individually at 40kph at the same throttle position. Sure, the other balancer gauges probably work fine, but they only prove each jug is pulling the same torr (mmHg/vacuum). I've never used one before, but I feel balancing tools may not really give an indication of real-world performance based results in all situations (mostly with a crappy old bike or one not fully broken in).

 

However, I would say the balancing tool would be useful as a diagnostic tool. If you balanced your carbs with the speedometer but your Twin Max/Carbstix showed something different, you may wanna investigate why.

 

A balancing tool assumes identical inputs of air in each jug will result in identical outputs on the crank. I'm saying that might not necessarily be so in all cases because there's probably lots of crazy stuff that can go on in each jug of a Ruskie engine besides air flow. I just think the best way to measure the real result of what each jug's true output is best done somewhere after the crankshaft (like the speedometer!!!).

 

I'm no mechanical genius but it does kinda make sense right?!?!?! :biggrin:

 

Plus, did I mention I'm too cheap to spring for the $4 el-cheapo kit and too lazy to tap out the carbs?!?!?!

Link to comment
Share on other sites

I personally think your factory installed speedometer is the best (and cheapest, and easiest) gauge for syncing carbs. It's a no-nonsense, real-world, performance based method with empirical results that should over rule all other methods for getting proper carb sync.

 

It just makes sense to me that you can't get no better sync-ed as long both sides are running individually at 40kph at the same throttle position. Sure, the other balancer gauges probably work fine, but they only prove each jug is pulling the same torr (mmHg/vacuum). I've never used one before, but I feel balancing tools may not really give an indication of real-world performance based results in all situations (mostly with a crappy old bike or one not fully broken in).

 

 

Plus, did I mention I'm too cheap to spring for the $4 el-cheapo kit and too lazy to tap out the carbs?!?!?!

 

ok for 650s with points to balance each cylinder by pulling the plug leads at a set throttle speed of 40kph but i'm not risking that with electronic ignition something WILL get FRIED thats why i'll get some sort of balancing gauge

Link to comment
Share on other sites

I was told by one of the "big" Ural dealers that pulling a plug wire on the type IV/type V ignitions was a no no. With the wasted spark system I figured the coil would discharge just fine, but I was never willing to take a chance and try.

 

Are you shorting the plug wire to ground or just pulling it?

Link to comment
Share on other sites

I pull the wires off and short 'em to the engine block.

 

However, I've noticed that since I set the air gap on the coil between the spark plug lugs and the pointy metal tabs to 3/8'' like the 1998 Ural manual says, that a big fat spark will appear there when you unplug a wire or the plug fails to fire for any reason. It would've been a nice diagnostic tool to know when I had a plug wire go bad rather than me thinking that the spark there was the problem. Without this gap set, when my plug wire went bad, that big fat spark was jumping back into the the module's output connectors.

 

I've ohmed the tabs out and they aren't shorted directly to ground. They give increasing readings to ground like a reactive component and are electronically isolated from everything else. I'm not certain of the function of these tabs as I haven't seen them on any other coils. The only plausible explanation I can think of is that it's protection circuitry with a dual purpose to (1) keep the coil from overheating by giving spark an alternative path to electron hell (ground) and (2) not burning a path through your EI module through the nearby connectors.

 

Anybody got a better explanation for the air gap???

Link to comment
Share on other sites

To the electro-foilheads:

 

I've developed a digital balancer. 2 MPX2200 vacuum sensors are needed, 2 DC/DC converters, 2 instr. amplifyers, and a PIC microcontroller. If anybody is interested, I can send the schematic drawings, .brd files, and the source code for the PIC. The display is a 2x20 char LCD. The upper line shows the vacuum values in mBar, the lower line some instructions are printed, what to do (Decrease left cylinder screw, etc.) I've adjusted 10 mBar raster. The device is very-very accurate, and doesn't need any adjustement while balancing, such as the analogue ones need adjusting on idle and raised throttle. It is fully automatical.

Link to comment
Share on other sites

What did it cost you to make this?

 

To the electro-foilheads:

 

I've developed a digital balancer. 2 MPX2200 vacuum sensors are needed, 2 DC/DC converters, 2 instr. amplifyers, and a PIC microcontroller. If anybody is interested, I can send the schematic drawings, .brd files, and the source code for the PIC. The display is a 2x20 char LCD. The upper line shows the vacuum values in mBar, the lower line some instructions are printed, what to do (Decrease left cylinder screw, etc.) I've adjusted 10 mBar raster. The device is very-very accurate, and doesn't need any adjustement while balancing, such as the analogue ones need adjusting on idle and raised throttle. It is fully automatical.

Link to comment
Share on other sites

Not much, I had most of the parts in my drawer. :unsure2: Some good free sample parts. :laugh: I only paid 4 USD for the display, and about 9 USD for some parts, which I didn't have.

 

If all the parts would have been bought, it would cost about 200 USD.

 

 

The pictures were taken durint the test-phase, it's in much advanced state now.

 

post-4323-1209480819_thumb.jpg

post-4323-1209480853_thumb.jpg

post-4323-1209480875_thumb.jpg

 

What did it cost you to make this?
Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

Loading...
 Share

×
×
  • Create New...