Valk running rough

[mat4uscg]

I have a 97 Tourer. Yesterday I gassed up and the bike begin to run rough about 4 miles later. I first noticed the idle RPM had dropped off and was unstable. Acceleration is still pretty good but holding a constant throttle at 2K RPM the bike has a noticeable miss. I just topped off the tank and added Sea Foam. I have about 40 miles on that tnak and no god results as of yet. Anything else I should be looking for?

Thanks

[Chrisj CMA]

Well, for a '97.....it should have had all vacuum lines replaced at least once.  The petcock (if stock) is due to be failing, and have you tightened the upper and lower intake clamps on all six intakes?

Lets, see........you can try a can of seafoam.  And, maybe the fuel filter screen in the tank is gunked up.

Im thinking if you have done all this stuff and are sure of the work, then it sounds like bad gas.  Seafoam and ride, and see what you get....

[Patrick]

I agree,, it sounds like maybe you got a tank of bad fuel.. Why not try to drain the tank and carburetors and see if that fixes it..

[mat4uscg]

I went ahead and de-smoged the Valk while I had the breather out. I checked the pet rooster and it seemed to be okay, good flow when I apply vacuum. I did notice that with a hand vac pump the valve would leak off the vacuum pretty quick. I am going to swap to the Pingle and an electric valve just to be sure while I have it apart. I did drain the tank but how do I drain the carbs? Anyone think if any thing I missed. By the way I did start it earlier today before disassembly and while it was choked it ran great, very smooth. Once the choke came off it dropped very low in idle speed and had the miss again, sounds like a fuel problem but wonder if anyone has a other ideas.

Thanks,
Tim

[Patrick]

There is a drain screw[regular flat-head] on the bottom of each carburetor.. Drain 'em and when you get new fuel in the tank run some of it thru the lines and carburetors [with the drain screws open]..

[mat4uscg]

Are these the flat head screws facing you when looking at the bottom of the carb?

[MP]

It should HOLD vacuum.  If it bled off fairly quickly, the diaphram is leaking, and needs replacing. 

MP

[Patrick]

Yep, the drain screws are fairly easy to locate/see and sit somewhat horizontally. They should have a black flex line attached to them to leads to the rear of the engine[unless someone removed them].. Now, it is quite possible that you did have a petcock failure about the same time you got fuel so it'll probably be a good idea to check both items.. 

[mat4uscg]

Okay. I de-smoged, replaced all vacuum caps, and installed a Pingle valve. Same problem exists. Starts great and runs smooth with choke on. Once the choke comes off then idle speed drops off and the miss returns. Good acceleration but cruise bounces all over with a very noticeable miss and slight lurch. Any ideas?

[Patrick]

Well, you didn't say whether or not you replaced the fuel and flushed the float chambers.. If you did, then it sounds from what you now say that you may have a case of the infamous clogged low jets.. Try a few good heavy doses of sea-foam and see what happens..If that doesn't work then it looks like the carburetors need to come apart..

[mat4uscg]

Patrick,
I did drain the carbs and flushed them. New gas with  dose of Sea Foam and no luck. High speed is good but steady and idle are still bad. Can the low jets be removed and cleaned with carbs in place?

Thanks,
Tim

[dreamaker]

Yes it can I have done it several times, you just kinda depend on feel, but it not that bad. Make sure you use the correct bit for the Japanese style screw. People mistake them for Phillips head and strip them. Don't quote me on this but I think it is called JIS bit, I maybe wrong on the name. I found it allot easier to do them on the bike rather then pulling the carbs. Here is some pics to give you an idea what you will be looking at and some tools I use. I got them at the local auto part store.


Dan



Hope this helps !!!

[John U.]

Here's a link for the JIS bits: http://www.jergensinc.com/infodir/catalog_asg.asp?GroupNum=305
If you have slow jets that won't clean, like I did, http://sudco.com/ has the stock slow jets (35's) or the 38's that a lot of us have replaced them with.
Good luck, let us know how it goes.

[John U.]

I forgot to mention that the "D" bit shown attached to the tool in the photo above is for the pilot screws. You can get that at MotionPro.com

[Patrick]

Yep Tim,, Like Dan and John have said, you can get at the jets by removing the intake runners and the float chambers.. Some guys have had trouble cleaning the jets,but, they should clean up with some air, tag wire and a good carburetor cleaner like deep-creap[spray version of sea-foam]..If they do require replacing then like the guys said, Sudco has them.. If you stick with the 35s then the pilots will work fine when set at 2.25 turns and if changing to the 38s then 1.5 turns seems about right.. Once the pilots are out, I cut a slot in them for a regular screwdriver and add a dab[technical term] of never-seize to the threads..

[dreamaker]

If I may suggest, if you are considering jets, I got mine from Chaparral they are the same jet as Sudco but almost a dollar cheaper each. I got mine and on the package was the Sudco number on it.  I bought a backup set, so if my jets ever get clogged and I have to soak them I just change them out rather then having the bike sit for two or three days.

Dan


http://www.chaparral-racing.com/Chaparral/product_family.asp?family%5Fid=11180&gift=False&mscssid=CAD394AF242448D78383D8AE5FFA68D0

[longrider]

Tim

Lot of good info here but just before you take it all apart try this.  squeeze shut the two vacuum lines  off the intake runners on 3 and 4.  I installed new lows and adjusted and  sync'd to get a smooth idle.  After startup the engine had a severe miss.  It was getting air through the emissions system.

warren

[mat4uscg]

Warren,
I removed the pair valve and all associated vacuum lines. I am working 7 12's which leaves me very little time to work on the bike. Been on this schedule since Jan. I may just take it in and let the dealer clean the carbs. They quoted 550.00 for a complete carb clean and engine service.

Tim

[Beast]

I had a similar problem yesterday
the idle speed dropped off and the bike just wasn't that smooth......... felt like I was running out of gas and needed to set the petcock to reserve........so I did and it didn't help.
So I put some full cleaner in the fuel ( Chevron with Techron fuel system cleaner, very good stuff) and started to pull the spark plugs for inspection the second one I pulled had a piece of carbon stuck across the gap on the ground strap......couldn't blow it out had to get it out with a feller gauge.

Earlier I had made a blast..........it probably loosened some carbon

Check those plugs

Dave

[mat4uscg]

Dave,
         Thanks for the input. I changed the plugs this past week but did not see any problem on the ones I removed. Seemed they were a bit white indicating a lean condition but not bad otherwise.

Tim

[mat4uscg]

FINAL RESOLUTION: I did have the dealer look at the bike and he cleaned the carbs (off the bike) and did a complete tune-up. I looked at the dirty carbs and here was some very visible blockage in the jets. Runs great  now. I appreciate all the help!!

Thanks,
Tim