Rough running

[VALKen]

Even having drained the carbs prior to winter storage, when restarting the Valk in the Spring, it runs very rough low down. Seems to tick over OK, but as you try to pull away it is clear it's down to running on less than all 6, then as the revs build the other cylinders seem to chime in. It's kinda what I would expect it to do for a short while, but it doesn't completely go away.

Now I realise it's likely to be gummy carbs, but before I hack into that, has anyone got any alternative suggestions? Have others had the same problem and had to clean out their carbs to get it running right again?

[R J]

SeaFoam, Techron (sp) and any other product that will desolve crude in the jets.

Did you have anything in the gas when it was put up for the winter?

If not, you might just have BAD Gas.

[Bighead]

I would hope since the carbs were drained that the tank was empty?
Or at least had some stabilizer in the gas.

[sandy]

Probably clogged low speed jets. Remove the pilot screws and spray some Yamaha spray carb cleaner into the holes. Replace the screws, set at 2 1/4 turns out from lightly seated.

[Michvalk]

Just pour the whole can of seafoam in and fill the tank with gas. Ride some low speed for a while, turning on the choke once in a while. Let sit overnight and ride some more. Should clear up after a bit

[R J]

Just pour the whole can of seafoam in and fill the tank with gas. Ride some low speed for a while, turning on the choke once in a while. Let sit overnight and ride some more. Should clear up after a bit

I totally agree with you 100%.      In 243K+ miles I've only had my carbs out once.

I learned of SeaFoam in Florida one time during Bike Week.    MGM was running horrible, it wouldn't even get out of it's own way, I pulled into a Parts Store and asked the counter guy what he had for a sluggish engine.    He pointed it out to me.    I bought it, while my son was paying for it, I was adding it to MGM.     He came flying through the door when I tossed the empty can in the trash.    He said man you are only supposed to use, forgot how many ounces now, told him tough, it is in there now.    I still use a full can when I need it or storing it.

[pancho]

I agree also,, except I would use a can of Berrymans B12.. $3 at Walmart and works great.

[salty1]

I agree also,, except I would use a can of Berrymans B12.. $3 at Walmart and works great.

    Berrymans Chemtool is my favorite and I use a full can to a tank every couple of months. Once the cocktail is mixed I ride it out in a day outing. Haven't had carb issues in a very longtime.

Techron and SeaFoam are also good products, but I just feel Chemtool  " scrubs" best. I have no empirical evidence to back up my claim. It works for me.

[VALKen]

It's not just bad fuel. Not only is that something I've never experienced in over 40 years of riding, but the problem persists through many tanks of fresh fuel. It's occurred the last couple of years and has improved each time during the summer to the point where I couldn't be bothered to do anything about it. But it seems to take longer each summer and now feels worse than in previous years.

I guess first thing to try would be some cleaner. Anyone know what's available over here in the the UK? No doubt none of your suggestions will be available in the local Halfords. 

[Skinhead]

Techron should be available it is made by Chevron, I believe Stoddard solvent is pretty much the same thing.

[VALKen]

Techron should be available it is made by Chevron, I believe Stoddard solvent is pretty much the same thing.

Thanks for that. I'll have a look today.

[R J]

If ya find something along the line of what we use, pour in the whole can, run it the first 40 to 50 kilometers below 3,000 rpm's, so as it keep the treatment in the slow jets as long as possible.    Then kick it in the butt a few times, or run in the R's above 3,000 RPM's, to clean on the fast jets.

Bring the bike back home slowly.   This is to get petro in the slow jets again.

Let it set overnight or as long as ya can, like overnight and into the next day or longer.

Give the petro treatment as long as possible to do it's thing, before ya try it again.

It might take 2 or 3 sessions of this before it will be clear.

It has worked for me several times in 243K+ miles on MGM.

Good Luck.

Also, when cold weather comes and you park the bike, pour a can of whatever you use in a fresh full tank of petro.    Run it long enough, on the street, to get your mixture into the carb bowls.    When spring rolls around, take the old girl out and run it like ya stole it.   The next tank of Petro add a full can in it.   

Any time you think it is sluggish, put a can in the pretro. 

About 1/2 way through your riding season, you might toss a full can into your fresh tank of Petro. 

[VALKen]

Well I actually found my local shop sells SeaFoam, so I poured in 2/3 can and filled up. Rode about 100mls yesterday and I would say it was beginning to feel a bit different, but it is still very bad just off idle. It's now had more time to sit and I'll run it up briefly today to flow a bit more through, but not able to go out for a ride today although it's surprisingly great biking weather at the moment. Unusual to want to ride in March here in the UK, but it's been pretty good for about a week now.

I was thinking regular treatment might be a good idea, but it would get rather expensive. I don't know what SeaFoam costs over there, but I bet it's a lot less than the £15 I had to pay here. That's $25 plus another $40 for the petrol, makes an expensive fill up for us. 

I still need to see that it actually works. In any case, I'm quite interested in looking into the practicality of fitting fuel injection. I know it's been done, but each attempt is very much a one-off. Would be nice if there was a kit one could buy.

[gordonv]

There are times when one carb cleaner additive will not clean all the problem.

So don't bother more that twice with any one carb cleaner, find another, and do the same thing.

It can take as much as or more than 3 types of cleaners. If you have Techron in your petrol at Chevron, then change your fuel to that, and just enjoy the bike.

Remember to use a fuel stabilizer when storing for the winter. You should have a little less issue in the start of riding season.

Oh, and maybe post your findings of the types of carb cleaners you find for others overseas. I wonder if these things could be ordered online and shipped?

[Conrad]

I'm guessing I have the same problem.  After sitting up during the winter it's running like crap, seems to be worse on the left hand side (that side being down on the kick stand).  It seems to smooth out a bit if I put on the choke just a little.  Added a can of Seafoam and going to ride tomorrow after the rain quits.   I'm hoping this does it.   It's hurting my soul that it's not running right.

[R J]

I'm guessing I have the same problem.  After sitting up during the winter it's running like crap, seems to be worse on the left hand side (that side being down on the kick stand).  It seems to smooth out a bit if I put on the choke just a little.  Added a can of Seafoam and going to ride tomorrow after the rain quits.   I'm hoping this does it.   It's hurting my soul that it's not running right.

Be sure and run it in the low RPM's to get the mixture in the slow jets.   Ride it home slow, and let it set up all night.  Use a 2X4 under the kickstand to make the old girl set up a little straighter.

You might have to do this a few times to get all the crap out of the jets.   I know mine every once in awhile it takes 3 or 4 treatments on the overnight.   Usually overnight will let it get into the jet and it will soak some of the crude off.

I'm still running the EOM slow and fast jets.    Got a very responsive throttle also.

[paps350]

 I use Techron only because it works for me. I hate to admit I don't ride as often as I would like so even during riding season I use Stabile in the tank. If I forget ( and I do) and it runs bad I dump an entire bottle in the tank and ride as everyone else recommends. I always start the season with Techron also.

[signart]

I don't know about the rest of you, but I can't see putting 3 tanks of fuel and 3 cans of wallet cleaner through my Valkyrie (about 450 mi.) with it running like crap when I know what it's supposed run like. You can down those carbs in less time, clean out the jets, the bowls, the tank, and go over a ton of maintenance issues at the same time. Then you can enjoy your Valk and sleep at night. There are times when opening a can just won't do it.
By the way you can buy a set of 38's for what you spend on 3-4 cans of seafoam.

[Ricky-D]

With ethanol enriched gasoline being the new normal these days,

a wise prevention is to use an additive in the tank every now and then.

Even auto manufacturers suggest an additive in the tank occasionally.

Prevention is the smart move, and prevention saves a lot of time that

would otherwise be spent fixing, cleaning and replacing parts, not to

mention the money saved and aggravation avoided.

***

[Patrick]

Well I actually found my local shop sells SeaFoam, so I poured in 2/3 can and filled up. Rode about 100mls yesterday and I would say it was beginning to feel a bit different, but it is still very bad just off idle. It's now had more time to sit and I'll run it up briefly today to flow a bit more through, but not able to go out for a ride today although it's surprisingly great biking weather at the moment. Unusual to want to ride in March here in the UK, but it's been pretty good for about a week now.

I was thinking regular treatment might be a good idea, but it would get rather expensive. I don't know what SeaFoam costs over there, but I bet it's a lot less than the £15 I had to pay here. That's $25 plus another $40 for the petrol, makes an expensive fill up for us. 

I still need to see that it actually works. In any case, I'm quite interested in looking into the practicality of fitting fuel injection. I know it's been done, but each attempt is very much a one-off. Would be nice if there was a kit one could buy.

You need to give it a chance. Some of us have been riding these monsters for a long time. Do what RJ says, run it at low engine speeds and it should keep clearing up. But, if you want to get your hands dirty go ahead and clean things up. Its an experience I'm sure you'll enjoy.