Magna Owners Of Texas

I am new to the V65 but have riden smaller (250 cc or less) motorcycles for many years.  So this set of questions is aimed at riders with experience on V65s.

I just bought an 84 V65  Magna with about 22K miles.   The bike seems to be running good.  It starts well.  The throttle resonse is good.  Idle is smoth even just after starting.

My question has to do with MPG.  I just took the bike on a 1,500 mile trip on interstate highways.  My speed was between 70-80.  I have a windshield.  I was geeting between 25 and 30 mpg.  In town with speeds under 50 I have gotten closer to 35 mpg.

Here are my questions:

1. Should I get better milage?  If so how much?  I have seen claims of 35 to 40 on this board.

2. Should I worry about this milage?  I have no desire to increase the power on this bike.  It has plenty now.

3.  Assuming the mpg is low what cost effect measares can I take to return it to better mpg?  

The power is not an issue to me.  This bike has more power than I need.    I would just like to increase the mpg and the range.    

Currently I also ride a 250 Rebel and the mpg drops to 60 on the highway.  Of course the Rebel does not have near the power.

I get 38 to 41 on mine on trips.  Around town I cant get off the throttle and she drops quite a bit.

Bryan

I have an 83 V65 Magna that I will get 40-42 on the highway and 35ish in town.  I would say that your mpg is a bit lower than most I have heard.

If everything is running smooth I would not worry about it unless you feel the mpg is too low and want to look into matters.  I would start off with the usual (plugs, fuel filter, air filter, etc...) just like a car, the newer all those items are the better mileage you normally get.  If that doesn't help and you feel real ambitious you could pull the carbs and see if some previous owner had shimmed the needles in the carbs or put bigger jets in.  Both of those items would decrease fuel mileage but give you more power.  I would try the small items first and see if that helps.  After that it is up to you.  Pulling the carbs is a bit of work and you may find that no one had modified the carbs.

Good luck.   :)

The 70-80 speeds will hurt your fuel economy a bit but not that much I dont think.
I would check all the things previously mentioned as well as make sure you tire pressures are up to suggested range from tire manufactuer.
Pull the plugs and see what they look like that will tell a lot, you want then golden brown.  My guess is you will find some or all to be dark brown/black suggesting dirty air filter, possibly weak ignition, other things all ready mentioned.
Do you know if the bike has stock exhaust?

Thank you Antman and Greg:

I have a stock exhaust system.  It looks just like the one in the 1983 add.  So I doubt that other modifcations were made.

I pulled the plugs and all the insulator on the center electrode looks the same on all 4.  One side of the insulator is white and looks nearly new.  The other side has light brown coating on it.   The top electrode has a gray to light gray coating.  The rim around the electrodes is here the differences are.  Plug 1 & 2 have a little black coating.  Plug 4 has a thick back coating., almost wet looking.  Plug 3 has a light gray coating on the rim.  Any idea why the difference between 3 & 4?  Is 4 burning hotter than 3?

The plugs are trying to tell me the history of the firing in the chambers.   I just can not understand them.  They do not look like they are shorting out.

I pulled the air filter and it is a dirty paper filter.  Looks like it is time for a K&N filter I can clean.

Your plugs could look different due to many different things (deposits in your cylinder, different compression, etc...).  I would run a tank of gas through the bike with a bottle of Seafoam carb cleaner (buy at any auto parts store).  That should help remove any build up and deposits, then change all your plugs, fuel filter, and air filter.  See what that does.  After a few hundred miles with all new pull the plugs again and see if they still look different or if they are all the same golden brown like Greg recommended.

Best of luck.  I just filled up today and got 38mpg on a tank that was all in town driving.

Later,

Anthony

I would if it were mine, replace air filter, plugs, all fluids, pull carbs and clean the slow speed jets and inspect things.  
And check for improvements and such, if things still did not improve drastically I would adjust the valves.
The wet plug is not burning completely or is getting too much fuel due to a number of things.  If your air filter is dirty this could be the cause, the V65 has 2 different vacuum slide spring rates for front carbs versus rear carbs.  If someone had it apart and swapped those then this also could cause issues.
This should be enough information to get you well on your way to learning a great deal about your new ride.

Thanks a bunch for the help.

I think I will start with the carb cleaner, plugs and air filter.  Then see what happens after that.

Gary I have a wrench session scheduled for the 19th of this month, be glad to help ya do the carbs if ya want.

I ride an '86 V65.  You should be getting anywhere from mid 40's to low 50's on the highway running 70-75mph.  I ride mine to work which is all short trips and I get around 32 - 35 depending on how much I twist my wrist.  I never get less than 45mpg on the highway and have had has high as 51mpg.  Need to start checking some things out.

OK I have changed the oil and filter.  The oil was nearly black so it was time.  I changed the air filter with a new paper filter from Honda.  I changed the fuel filter, it was full of rusty looking stuff.  

I bought a bottle of Sea Foam.  What do you suggest?  Pour the whol bottle in the tank?  Should I pour some directly into the carburetors?  If so what is the best way to get it directly into the carb?

It sounds like the carbs is a good place to start.  It looks like I have to take off the tank to get the carbs off.  Sounds like I might as well go ahead and remove the radiator and check the vavles while I have everything apart.  I have checked and adjusted valves on VW bugs and Rebels. many times.  I am not stranger to vavles it is just all the tings that need to be pulled to get down to the valves.

I assume that the rich condition indicated by the dark plugs would would be big waster of fuel.  The electrodes on the plugs look fine but at $3 per plug I went ahead and got some new ones.  Should I wait to get the carb problem resolved before I replace the plugs?

I may have access to a compression guage I can use to test the cylinders.

Thanks for the input.

If your fuel filter is full of rust you may want to take a look at the inside of your tank.  If there is a lot of rust and scale you can use a product called POR 15 to treat and seal the tank.  I did it and it is really easy.  It comes with an etching solution to stop the rust then a coating to completely seal the tank.  I did the secondary tank as well.  One trick I found was to hook a fish tank pump to the vent line so the sealer didn't plug off the vent.

To do your carbs it is easiest to remove the tank.  You need to remove the airbox and filter before you take the carbs off.  It will be much easier for the carbs and the valve adjustment if you remove the radiator as well.  Since it is pretty easy to remove I would do that and change your coolant at the same time.  Getting the carbs out is pretty easy, getting them back in was a pain.  An extra hand or two would be helpful.  Most auto parts stores sell carb cleaner in a one gallon can that comes with a screen tray.  This allows you to take one carb apart and set it in the tray and soak it to clean it.  Very helpful.  Do one at a time so as not to mix them up.

If you plan to change all your fuel lines I would forget about the seafoam.  If you do not plan to change all your fuel lines I would pour it in the tank to try to clean out the lines.  No reason to focus the cleaner on the carbs since you will be pulling them and cleaning them at that time.

If you are near McKinney I could give you a hand.  I will be gone this weekend, but evening and most of the following weekends are open.

Good Luck,

Anthony

There may be an easier and safer way to clean out your gas tank. I have not used this product but came across it when doing some research.

It's an environmentally friendly rust dissolver that will not harm paint or chrome. You can read a review about how well it worked on motorcycle tanks here:
www.motorcyclecruiser.com/tech/rust_removal/index.html

Here's the company:
www.rusteco.com

If you try it, let us know how it works for you.

I hear good things about Kreem product.

I've used the Kreem product to remove and re-line/seal a tank on an old '73 CB350 that sat for 20 years. Easy to use 3 step; etcher, cleaner, sealer. It removed large rust problems and resealed the tank good as new.
Just be sure to use those rubber chemical gloves and safety glasses [can get from the hw store] as the etcher chemical fluid [phosphoric acid]is highly acidic and can burn skin and eyes.
You'll also need to get a couple of empty 5 gallon plastic buckets to empty the tank post etch and post etch wash down. This bucket will have to go to a hazarous household waste collection point that many suburbs have annually to pick stuff like this. [make sure to keep the labels or bottles so the haz folks know whats in the bucket !]
Also large 3" dia rubber plugs can be had a hw or hobby store ; used to plug the gas fill hole when turning tank over for etching; and smaller plugs for the petcock hole.

Really its pretty easy and straight forward and produces a great result.

I have used Kreeme on tank before.  It seemed to work.  That was about 20 years ago when I worked on that bike.

I will try the Sea Foam to see if that will work.  (Probably not but I already payed for it.)

I will be out of town for a while before I can start on this project.  

Just out of curiosity is it possible that varnish could cause the carb to run rich.  If so how?

Thanks for your input.

Here is an update on my v65.  I replaced the air filter, fuel filter, changed the oil and replaced the oil filter.  I ran a can of Sea Foam though the tank.  I took of the air cleaner and upper air box and sprayed carburetor cleaner into the carbs.  I changed the spark plugs.

The last tank I ran I got 35 mpg before I was getting 25 mpg.  This is a big improvement.  Much more like what I have seen for bikes of this displacement and level of performance.

Gary probably wont make it run rich, however will decrease performance if bad enough, and cause you to twist more to overcome it and could drop fuel economy.

If the 35MPG you got was some in town and some highway I would say you are right were you should hope to be.  If you were all highway miles then you may be able to get a bit more by going through and adjusting your carbs.  Small adjustments on the pilot screws, carb sync, etc... can all add up.  

Glad to hear you are saving gas now that it is near $2...   :D

Anthony