Carb Question

[MikeZ06Allen]

Ok folks this is my first "official post" and I am new to the VR so I hope my question isn't too far in left field. Keep in mind I am a child of the fuel injection generation so carbs are a balck art to me. I can tune the pants of a fuel injected vehicle, case in point my 500 HP Vette, but carbs befuddle me.

 

So my question: Recently I put some holes ( about 8 x 3/8 inch) in the stock air box and noticed a little improvement. Last weekend I decided I needed a little more agressive sound so I cut-off the end of the muffler and removed the end baffle. The inner baffle is still intact and I love the new sound. So is it possible with some loss of restriction on the airbox and muffler side that I need to put bigger jets in the carbs?

 

The bike is purring like a kitten when cruising down the road, no pops or back fires and much better acceleration but I also want it to last and really don't want to melt down valves or pistons due to an over lean condition.

 

My first Touring bike and I love it.

 

Thanks

Edited August 31, 2010 by MikeZ06Allen

[GeorgeS]

As a general rule of thumb, its best not to mess with these carbs.

( other then normal maintenance )

 

Just be sure your linkage assembly is Sync'd properly ( See maint manuel, on line this site, if you don't have one )

 

Some have made minor adjustments by shimming the needle valves on the Carb Pistons. But as I understand it this is manily to improve fuel economey. But if you are getting about 40 MPG + or - thats about normal.

 

If your in the low 30 MPG range, then you might start looking for some problems.

However if near 40MPG, and your plug readings look good, and performance is normal I would leave the carbs alone.

 

You might check the settings of the " Idle Mixture Adjustment Jets " if you have not yet done so. ( Also the condx of your rubber diaphrams, check for damaged rubber )

[safetyguy]

As a general rule of thumb, its best not to mess with these carbs.

( other then normal maintenance )

 

Just be sure your linkage assembly is Sync'd properly ( See maint manuel, on line this site, if you don't have one )

 

Some have made minor adjustments by shimming the needle valves on the Carb Pistons. But as I understand it this is manily to improve fuel economey. But if you are getting about 40 MPG + or - thats about normal.

 

If your in the low 30 MPG range, then you might start looking for some problems.

However if near 40MPG, and your plug readings look good, and performance is normal I would leave the carbs alone.

 

You might check the settings of the " Idle Mixture Adjustment Jets " if you have not yet done so. ( Also the condx of your rubber diaphrams, check for damaged rubber )

 

 

This is all good advice -- it is better to have a running bike than to make one too many modification and THEN have to figure out how to get things running again & where to buy replacement parts for 20+ year old Ventures.

[MikeZ06Allen]

Very good points but it also good to have a bike that is running in the safe zone. I know first hand what a lean mixture can do to an engine and I do not want that to happen to my VR. I did notice the bike seemed to struggle much above 85 mph today. Might be because it was flippin 97 degrees here in VA.

 

Thanks for the advice. Now where did I put that socket wrench? I am off to get a plug reading.