Update on Improved Gas Milage After Mods!

[skydoc_17]

When I purchased my 87'VR last winter I was getting 31 MPG one up and 28-29- MPG two up. Needless to say, I was not impressed! Over the winter of 08' I did a few repairs, mods and after about 1000 miles I can now say for sure that my gas mileage is much better. Here is a list of the mods:

 

1) Carb. Diaphragms (when I pulled mine, they looked like spaghetti strainers! I just replaced the rubbers, NOT the sliders)

2) Needle Shim Mod from 5Bikes ( Removed Nylon spacer and replaced with S.S. washers, .050 thinner than Nylon spacer)

3) Crankcase Vent Mod ( plugged airbox, removed vent tubing, installed Crankcase vent filter)

4) Carb. Sync (purchased Carbtune and Synced Carbs. Built a "manifold" to verify Carbtune accuracy.)

5) Adjusted Mixture to 2 1/2 turns from bottom

6) New Plugs

7) New Wires (from Ebay)

The bike starts great, runs like a scalded cat, Idle is great, no more soot on tail pipes, no "Backfire".

Over the last 4 tankfuls of gas, I have been getting 180 to 190 miles before the "Red Light" comes on. ( 4.0 gals. 45 to 47 MPG) This is one up. Two up I got 165 to 175 miles on three tankfuls. (4.0 gals. 41 to 43 MPG)

Thats roughly a 33% increase in gas mileage! Plus, I did most of the work over the winter so I didn't loose any riding time. There are many folks I need to thank and you rascals know who you are!

If you have questions, Just ask! I sure did and got a lot of great help!

Thanks to everyone,

Earl

Edited April 28, 2009 by skydoc_17
CRAYON BROKE!

[Evan]

Compliments to you on your work that improved your mileage so much and your report. Just acquired my first VR after owning and riding many other bikes, so this info is great. Any thoughts on which items had helped most?

[mbrood]

I would always add... "individual results may vary"

 

First thing is to check your plugs. If after a day of "normal riding" your plugs are sooty and black... moving the needles out is a good first step (leaner mixture). If your plugs are a nice light brown, this is probably NOT the mod for you. If the plugs are dusty white, you probably need to move the needles IN a bit... rather rare though.

 

Carb sysc is ALWAYS important. I worked on one that the guy had "synced by ear"... it seemed to run ok and idled "fair" except the transition from idle was real bad and the idle screw was screwed in a LONG way. It was so out of actual sync that two cylinders were basically carrying the load.

[Skid]

Always better to get more gas mileage. I mostly get from 45 to 47 as long as I keep out of the throttle whether I'm running one up or two. The diaphragms makes a big difference....

[5bikes]

I get disappointed if I don't get 45 mpg. Think how much cleaner the air is, your much heavier your wallet is, how much further you can go on a tankful, how much longer the engine and oil will last (cleaner burning), and reducing foreign oil imports if we all did this (ON ALL VEHICLES)!

Why I'm I the slowest vehicle on the road going the speed limit?

[RedRocket]

That's pretty impressive. I have seem to get about 35. I'm gonna try and improve it thanks to you!

[BradT]

How much better, curious minds want to know.

 

Congrats to your improvement.

 

Brad

[mmacpuguy]

Wow, how do you "sync" carburetors? Any videos that anyone knows of to help with these sorts of tasks?

[Freebird]

There is no video but there are step by step instructions here:

 

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

 

A video is not a bad idea. Maybe that is something that we can do in the near future.

[slick97spirit]

Here's a you tube video showing a guy doing the synch. It's not a 1st or 2nd gen but it gives you the general idea.

 

[ame=http://www.youtube.com/watch?v=CYgN2-96Ik0]YouTube - motorcycle carburetor balancing- Carbtune[/ame]

 

There's also a very informative thread that Freebird posted with photos that will guide you through the process.

Edited April 29, 2009 by slick97spirit
oops, forgot the link...here it is

[skydoc_17]

Hey Norm,

Welcome to the site. The object of the Carb. Sync. is to get all four Carbs. pulling the same Vacuum at idle. Syncing the First Gen. VR is actually much easier that the UTUBE video of the late model Bike the Brit was Syncing. Here is a link to the place where he got his Carbtune. This is what I use on my 86' and 87'VRs to Sync the Carbs.

 

http://www.carbtune.com/

 

Check it out, if you have any questions, just ask!

Earl

[Guest Swifty]

3) Crankcase Vent Mod ( plugged airbox, removed vent tubing, installed Crankcase vent filter)

Earl

...any chance of getting close up pics of that? Is the filter that red thing in the middle of pic #2?

[skydoc_17]

Hey Dave,

This project started when I put a K&N Air Filter in my 87'VR and the increased air flow started vacuuming oil vapor into the air box and contaminating the new K&N Air Filter I had just installed. Besides the benefit of no more oil in the airbox the other benefits were the Carbs. got a nice clean shot of air with no oil mist in it, which improved performance noticeably and if I keep out of the throttle, I got a gas mileage increase in the 2 to 3 MPG range.( *NOTE* Be prepared to catch he!! from some "tree huggers" over this mod!)

I have attached pics below, If you need more information, just ask!

Earl

Edited May 1, 2009 by skydoc_17

[CrazyHorse]

Hey Dave,

This project started when I put a K&N Air Filter in my 87'VR and the increased air flow started vacuuming oil vapor into the air box and contaminating the new K&N Air Filter I had just installed. Besides the benefit of no more oil in the airbox the other benefits were the Carbs. got a nice clean shot of air with no oil mist in it, which improved performance noticeably and if I keep out of the throttle, I got a gas mileage increase in the 2 to 3 MPG range.( *NOTE* Be prepared to catch he!! from some "tree huggers" over this mod!)

I have attached pics below, If you need more information, just ask!

Earl

 

Nice job I like it.

[TRnCO]

Where did you find that crankcase filter?

[Dragonslayer]

I did most of the things you had done except for the crank case vent filter and am anxious to see what the results are. I did the needle washer thing yesterday and it runs pretty good now. It runs like a raped ape instead of a scalded cat. I'm wonderering what the difference is in MPH and MPG.

 

Check out my carb bling.

[Dragonslayer]

...any chance of getting close up pics of that? Is the filter that red thing in the middle of pic #2?

Me too, inquiring minds want to know

[Dragonslayer]

Hey Dave,

This project started when I put a K&N Air Filter in my 87'VR and the increased air flow started vacuuming oil vapor into the air box and contaminating the new K&N Air Filter I had just installed. Besides the benefit of no more oil in the airbox the other benefits were the Carbs. got a nice clean shot of air with no oil mist in it, which improved performance noticeably and if I keep out of the throttle, I got a gas mileage increase in the 2 to 3 MPG range.( *NOTE* Be prepared to catch he!! from some "tree huggers" over this mod!)

I have attached pics below, If you need more information, just ask!

Earl

I need to do this manly because I hate fishing that Bannana twikie tube down thru the carbs and hooked up every time I take the airbox off. One of the most PITA task working on these carbs.

[skydoc_17]

Hey Bob,

I REALLY like your Carb. bling! I twist a pretty good wrench and machine things all the time for my scoots but all that "artsy" stuff is beyond me. My hat's off to ya'.

Now about the crank case mod, I tried a K&N crank case filter and because the diameter of the top of the filter was the same size as the bottom of the filter, it would not fit properly. I found a filter that fit just right from http://pics.ebaystatic.com/aw/pics/uk/s.gifautoperformanceonline they are located in the UK. You will want to purchase a filter that will slip on pretty easy. If it goes on tight you will never be able to get you hand in there and push on it hard enough to seat it. While I was in there I replaced the 22 year old coolant line with some really nifty clear hose I got from my local Yamaha dealer. It allows you to see the coolant flowing, now I can tell if my thermostate is working WITHOUT removing it. I will attach the pics of the upgrade again so you get an idea what it takes to get the job done. If you have any other questions, PM me. I think it's a great mod, and one that helps on a couple of different issues.

Earl

Edited May 12, 2009 by skydoc_17
CRAYON BROKE!

[PRAIRIECOOT]

I have done 1-4- 6 & 7 ordered filter 15 minutes ago

I am lost here - I have the carbs out have cleaned them

have bought "new " motor and ready to install

 

you refer to #3 as

""Needle Shim Mod from 5Bikes ( Removed Nylon spacer and replaced with S.S. washers, .050 thinner than Nylon spacer)""

 

#5 you mention

""Adjusted Mixture to 2 1/2 turns from bottom""

again - what does this mean

Thanx

merv

[skydoc_17]

Hey Merv,

I'm Impressed, most people don't pay much attention to me,(just ask Jean!) I will run thru the 5Bikes needle mod and the Idle mixture adjustment and with the pics supplied below you shouldn't have any problems, If so just PM me and I will help you all I can.

The needle mod: After removing all of the side plastic, you will expose the Carb. Body Caps (2 each) on both sides of your bike. After taking out the Diaphragms, Sliders, look into the slider and you will see a nylon screw with a flat blade screw slot in it. Remove this screw and the slider needle, a small spring, and the nylon "spacer" will come out. (*NOTE* These are pretty small parts and you will be chasing them all over your shop floor if you don't have this assembly on a bench where you can "catch" everything.) Remove the "Cir clip" from the needle, and remove the nylon "spacer". You will measure the thickness and decrease it by about .050" . I used #6 stainless steel washers for this.

Reassemble everything and you are good to go. After you run a tank of gas thru your bike, pull the plugs and look for a nice "tan" color on the plug. If it is black and wet,(too rich) remove a washer, if it is white, with no color at all, (too lean) add a washer. You might have to "play" with this a little.

 

Idle Mixture Screw Adjustment:I have attached a pic below with the location of the Idle mixture screw circled in red. Before I do this adjustment, I shoot a little WD40 in the hole. By the way, all of these adjustments are done with the bike OFF unless I say other wise.

You will do this to all four carbs. the same way and to the same setting. (keeping it simple) Take a small flat blade screwdriver and insert into the hole circled in red, rotate the screwdriver until you find the slot, very gently turn the screw clockwise until it bottoms out. (*WARNING* YOU ARE SEATING A NEEDLE INTO A SEAT, IF YOU CRANK THE NEEDLE TO HARD INTO THE SEAT, YOU WILL DAMAGE THE SEAT AND HAVE TO REPLACE THE CARB. BODY!) With that being said, I use two fingers and lightly seat the needle. Once this is done, turn the screw counterclockwise 2 1/2 turns. Do this to each Carb. This is a really good place to start and you may find that the screws are all over the place. If you have a decent digital tach. you can "fine tune" each screw for max rpm with the motor running at idle. This is a very tedious procedure and the 21/2 turns deal will get you pretty close. Here are some links that have some excellent pics in them and if you destroyed the cheap phillips head screws while taking the Carb. Caps off, try this link. http://www.venturerider.org/classifieds/showproduct.php/product/1643/cat/6

 

Here is the link to my write-up of the replacement of the Carb. Diaphragms with pics, you can use this to inspect the Diaphragms as well.

 

http://www.venturerider.org/forum/showthread.php?t=32052[/url]

 

 

Here is the link to my write-up of a Carb. Sync. using the Morgan Carbtune tool. You will use the same procedure no matter what type of Manometer you use.

 

http://www.venturerider.org/forum/sh...ad.php?t=35274

 

 

Merv, see the pics below, and if you have any other questions, just ask!

 

Earl

Edited May 14, 2009 by skydoc_17
Link To Carb. Diaphragm Replacement was bad!

[PRAIRIECOOT]

I am in the process of putting a 1300 in my 85 and I thot I might give this a whirl while I am at it

 

Ah =- Makes a bit-o-sense now

my carbs are off so it will be easier to do

I also have a extra set of carbs (in pieces )

so I can practice the settings/needles etc

thanx a million

 

Merv

 

 

 

 

 

 

 

 

 

 

 

 

9

[Dragonslayer]

Hey Merv,

Remove the "Cir clip" from the needle, and remove the nylon "spacer". You will measure the thickness and decrease it by about .050" . I used #6 stainless steel washers for this.

Reassemble everything and you are good to go. After you run a tank of gas thru your bike, pull the plugs and look for a nice "tan" color on the plug. If it is black and wet,(too rich) remove a washer, if it is white, with no color at all, (too lean) add a washer. You might have to "play" with this a little.

 

Here is where i have questions, Why do you say remove the cir clip. On mine that was not neccessary I could slide the nylon spacer off the needle point end without having to remove the c- clip. I had extra needles laying around, so the washer's i used were just the top side washers off those other needles so what I ended up with from needle point in was washer/c-clip/ washer/spring/Nylon cap screw. This improved the gas mileage from 20 mpg to about 28 mpg on first tank check.

 

Did I do it wrong?

[skydoc_17]

Hey Bob,

You did just fine. The set of needles in my 87'VR were roll stamped with a part number and I was not able to remove the nylon spacer without removing the cir-clip. I did not have any extra needles or washers so I took the needle to the hardware store and found that #6 stainless steel washer was pretty darn close to the metric washers on the topside of the cir-clip. The only thing I would suggest to you now is to keep a eye on your plugs and make sure they tan up a bit after a few tanks. If not, add a washer and all should be well. The washers I got are .025 thick and I was able to "kiss" another .005 off of them with an "India Stone" for the final adjustment that got me to 47MPG and still tanned the plug. The combo of the new Diaphragms, slider shim mod, crankcase vent mod, and a really good Carb. Sync. splitting the difference between idle and 3500 RPMs did the trick. I am going to Freebird's Maint. Day and will be traveling almost 1000 miles round trip and hope to really document the milage at that time.

I hope this clears this up for you,

Earl

[timgray]

I found a great site for reading motorcycle spark plugs....

 

http://www.angelfire.com/fl4/pontiacdude428/Readplugs.html