First Gear is Slowing Down

[mn_vette]

When I first got my 95 magna I had the carbs cleaned and the plugs changed by a certified honda dealer.  That was about one month and 1200 miles ago.  

I noticed that the bike would pull smoothly all the way through first gear when I first got the bike.  Then it would pull kind of slow and then get a couple of strong pulls around 5-6k then pull strong after that.  Now it feels slow and then kicks strong from 7k to redline.  

The other thing I've noticed is that the full choke warm up used to be just above 4k on the tach and now its around 3700.  

The bike also seems to need some throttle to get started now, not much, but it didn't need any when I first go the bike.

I've been running only 93 octane gas through the thing.  I do alot of highway driveing at 80mph and run it WOT just about every time I drive it.  

Is there something that is happening to the bike?  Is this just from the weather change?  I'm really hoping that I don't have to dump a bunch of money into it to make it run better.  

Thanks for the advice.

[DC Smith]

That sounds pretty much like a stock 3rd generation Magna.  Most have a surge around 5-6000 rpms.  You may want to put in shims and reset the pilot screws (which are set lean at the factory).  If you have aftermarket pipes you will also want to rejet.

As for the 93 octane, you are wasting money.  These bikes are designed for 87 octane and run better on it.

[mn_vette]

Is this something that the bike will develop over time/mileage?  It was running perfectly right after the carbs were cleaned out.  

I'll have to look into these shims and adjustments.  

The bike is totally stock by the way.

[Charles S Otwell]

I not big on a cure in a can, but while your working on the problem It sure wouldn't hurt to run some Sea Foam thru a couple of tanks, if you haven't already. The stuff really works well.

[mn_vette]

I not big on a cure in a can, but while your working on the problem It sure wouldn't hurt to run some Sea Foam thru a couple of tanks, if you haven't already. The stuff really works well.

Isn't Sea Foam a basic carb cleaner type additive?  If I've just had my carbs professionally cleaned a month ago would I really need this?  I was running 93 octane to try and prevent getting any kind of build up what so ever.

[DC Smith]

No, this is not something that builds up over time.  So if it ran perfect after the tuneup, it could be something else.   Most folks on here like to use an additive like SeaFoam every 4th or 5th tank to keep the carbs clean.  I'm no expert but I don't think burning premium is accomplishing what you want it to.  I fact it may be doing the opposite.   Try a double dose of SeaFoam on your next 2 tankfuls of regular 87 octane and see what happens.

[DaWood]

I thought I remember someone saying if you ran 93 octane in our bikes, you were likely to increase the carbon deposits on the plugs?  I had similar issues, but a fresh set of plugs made my bike run much better.  Having said that, how often do you guys replace your plugs?

[Greg Cothern]

Daniel, I replace plugs when I notice the fuel economy and power starting to sag some.  Of course this means keeping track of your MPG and such.


Mn_Vette sounds like a set of shims and pilot jet adjustment are in order.  The shims will richen the fuel/air ration in the mid-range where it is running lean.

[TLRam1]

I have 54k on mine and changed the plugs for the first time. Didn't help it but thought it was about time.

On 4-strokes, better gas, better oil, alloys, cleaner burning and tight tolerances plugs do not need to be changed as often as they once use to.

It does sound like carbs are partly clogged if nothing changed from before.

Depending on who cleaned the carbs, by that I mean your Certified Honda Dealer probably means a part time recently out of high school worker cleaned them, the quality of the job is reason to think it may not have been thoroughly done.  It is not unheard of you having issues after they work on it.

Using Seafoam or something equal may help if it is dissolvable, if not, the carbs may require another cleaning which at the time would be good to do the jetting if you have not done it by than.

[Magnum Magna]

Then it would pull kind of slow and then get a couple of strong pulls around 5-6k then pull strong after that.  Now it feels slow and then kicks strong from 7k to redline.  

The other thing I've noticed is that the full choke warm up used to be just above 4k on the tach and now its around 3700.  

.

How did it run before the cleaning and new plugs?

What is the condition of the inside of your tank?

Choking: First start of the day is the only time I use the choke.  Starts at 1200 and will slowly increase to 2000 or cold winter days I let the choke idle up to 2500.
Your normal hot running engin idle should be 900 - 1200 I believe. I keep my bike at 900.

5-6k then pull strong after that.:  I call it Turbo Time at 5k

[mn_vette]

How did it run before the cleaning and new plugs?

What is the condition of the inside of your tank?

Choking: First start of the day is the only time I use the choke.  Starts at 1200 and will slowly increase to 2000 or cold winter days I let the choke idle up to 2500.
Your normal hot running engin idle should be 900 - 1200 I believe. I keep my bike at 900.

5-6k then pull strong after that.:  I call it Turbo Time at 5k

When I bought the bike 1 month ago it didn't run at all.  The previous owner had put 200 miles on it in the last 8 years.  I trailered it to the honda dealer and they cleaned the carbs and changed the plugs and then it ran perfectly started with just a push of the start button.

From what I can see the inside of my tank looks just fine, no rust or anything.  I seem to be getting 40-46 mpg depending on how much highway and WOT driving I do.

So your choke only lets it idle up to 2.5k or so?  So I'm guessing the 3.5k I'm seeing now is not normal then.  My idle is also around 1500 rpm when its warmed up.  It sounds like something may be messed up in the carbs.  

Does anyone have a service manual that can look up the "recomended" idle and warm up rpm for the bike?

[DC Smith]

Idle at 1500 is way to fast.  There is an idle adjustment knob, and  the manual calls for 1000 (+/- 100).  Do you not have an owner's manual?  I would use the choke as little as possible.  My bike starts without the choke on all but the coldest days.  I use throttle to maintain 1200-1500 for a minute or two and then she's ready to go.  These bikes are not nearly as cold natured as other Hondas I have had.  There is really no recommended choke/warm up time, all bikes are a little different.  Again I would use as little choke as possible and ride it when you can get good throttle response.  Excessive idlling/choke seems to really foul things up on the Magna.

Your gas milage is right on.  If I ride 50-60 mph and use throttle gently, I can get 50mpg, but normal driving is around 45mpg.

I think there is a link to a service manual on the MOOT site, if not, someone will chime in with where you can find one.

[mn_vette]

well, I found the idle adjust screw and turned it down to just under 1k.  It definately sounds a bit meaner at idle now.  

I guess I'll have to see how things go after I run two tanks of sea foam through there.  I'll start using 87 octane as well.

[mn_vette]

Well, I'm half way through my second tank of sea foamed 87octane.  The WOT surge has gone away.  I guess I'll have to remember to not run the choke for very long and to run some sea foam through it every once in a while.  

Thanks for the help guys, I really appreciate it.  Its knowing these little things that keep this toy fun and not frustrating.  

[DC Smith]

Glad to hear it!!   How bout a pic of that purdy thang!!