Close But No Cigar

[mirion]

The before picture

After a major teardown I have got her back together but she ain't running right. I did a lot of cosmetic things such as new 6 degree front end but will only mention the things that might effect the running. I had it repainted which means I had a dry gas tank, did the new petcock cover thing, changed the intake o-rings, desmog, new Redeye diaphragm vacuum tube, new plugs. It seems like it isn't getting enough fuel. For the initial start with the choke fully on (and I mean fully) I pressed the starter button and after about 15 seconds it sputtered and ran but if I blip the throttle or touch the choke it quits. It will stay running at a very low RPM but I can't touch anything. I hoped it would warm up and start to run better but no such luck. The number 1-2-4-6 pipes are too hot to touch but 3 and 5 are cool. Looks like I am pulling the tank back off tomorrow but thought I would fish for some opinions. My biggest fear was electrical issues but the fact that it all the lights are working and it runs at all tells me that must be OK, I think??? Damn, it's nice outside and I wanted to ride this baby.......Thanks, Mike

[Bill anderson]

If there is ethenol in your gas and the carbs have been dry then they need to be thoroughly torn down and all passages cleaned. You can try running some Sea Foam thru them first but I think you'll have to tear them down.

[John U.]

A couple of cold pipes does sound like clogged slow jets, but those cylinders should fire with the choke on anyway. It's possible that you have a couple of stuck float valves and no gas is entering those carbs. Open the drain screws and see if you get any gas flowing. Rapping on the carbs with a screwdriver handle might loosen them. Some have tried a small shot of compressed air through the fuel line.
I think a heavy dose of Techron will do more good than Seafoam, but if these suggestions don't work, I'd say some carb work is likely. If the problem is clogged slows, you may get away with replacing the slow jets and spraying carb cleaner in the slow jet and in the pilot screw holes. Let us know how it works out.
Good luck, it still might be an easy fix.

[R J]

I don't know about the other 99.9% of the Valk's but you mess with the throttle on mine, when trying to start or after it starts until he is warmed up, it will die also..  I start pulling my choke back after about 2 1/2 minutes, very slowly, or it will die.   However, it will usually restart with the choke still set at where it died.  If it doesn't, full choke and crank.  Let it warm up some more.   I've started MGM in my garage which is unheated and it was -20* outside.  Full choke, key on, hit starter.   Will crank about 20 rev's and fire on 2 cylinders, then 2 more will kick in and final the last 2 will come alive.......  Only time it has failed to start in those conditions is when my firkin Battery Tender fried the battery.......

2 dead cylinders sound like clogged slow jets.   Common when ya drain them for the winter or painting and etc.  I park mine forthe winter with a full tank of gas, ethanol 10%, and a full can of Sea Foam.   Run the bike around the 4 mile circle from my house and back, to get the mixture into the carbs.    Pull him into his winter slot, shut him off, turn off the gas and put the cover over his sorry butt......

Now, suggestion for your bike:

Run a can of Techron or what ever it is called through it,  if that no work add a full can of SeaFoam to a full tank of gas and run that through it.

Still 2 dead cylinders, pull the carbs and go through all of them, jump up to 38 slow jets while you are in there......  I'm still on the original 35 jets.   Carb bank has only been pulled once, that was for a stuck adjustment screw......

[Valker]

Each coil controls two cylinders. Not sure how they are paired, but it might be worth a thought.

[ricoman]

I lean toward the slow jets also.
3 coils work cylinders in pairs on opposite sides. 1/2; 3/4; 5/6.

[RTaz]

Mike pull the carb bank...replace the slow jets...also make sure your floats are working correctly....also make sure your tank vent hole is not clogged...

[Ricky-D]

You should perform a compression test on the motor before attempting the tune out the problem.

If those two cylinders are not working properly (compression-wise) no amount of tweaking will bring them around!

***

[mirion]

As you advised, I opened the bowl drains and although there was a little wetness in 3 and 5 it didn't compare to what flowed out of the other four. Does this indicate a "stuck closed" float? Are there any "First try this" solutions without pulling the carb bank, I hate the thought of that. I tried tapping the bowls  as advised in hopes of loosening the float, no luck. What is the technique for blowing air down the fuel line. I do have the Cobra pipes but never rejetted, the guy I bought the pipes from included the Cobra jet kit but it seemed to run fine with the stock jets....Thanks for any and all suggestions.....Mike

[Tropic traveler]

I had the tank off for a week on my '99 project Valk & did some of the same things you did.
Bike was running fine beforehand just pulled it apart to clean & go over it real good.
Desmog, petcock cover set, replaced primary fuel & vacuum line, cleaned & gapped the plugs {they were fairly new} which means a dry tank restart. Fired it up yesterday but couldn't keep it idleing w/o the choke partially on. It would rev on 4 cylinders but rather sickly.
Anyways, after pulling 1 plug boot at a time I found it was cylinders 1 & 3 that weren't working. Left it idleing in the drive for a minute or two as I went to get my sunglasses from the house & took off down the road. Just one block away I got 1 cylinder back & by 2 blocks she was fireing on all 6.
I think it just takes a bit longer to get the fuel to flow to the RH carbs especially when the bike is on the side stand. Also how much fuel did you put in? More gallons means a heavier gravity push.
Try the easy & cheap stuff first!

   

[Daniel Meyer]

Check tank vent line for clogs or pinches.

Make sure you rebuilt the petcock correctly (got everything snapped together and sealed properly).

Make sure your new vacuum line is not collapsing.

Pull a vacuum on the petcock and make sure it holds it.

[mirion]

It turned out to be a simple issue, the petcock vacuum tube was kinked. I was so careful lowering the tank after connecting the vent line but the vac tube was snaggging on the electrical harness after I lost sight of it and I didn't know it, I feel dumb but so thankful I am not pulling the carb bank. It purrs like a kitten. Now to finish the rest of the chrome and try out the new 6 degree triple tree's. Thanks everyone for all of the input.....Mike

[TearlessTom]

It turned out to be a simple issue, the petcock vacuum tube was kinked. I was so careful lowering the tank after connecting the vent line but the vac tube was snaggging on the electrical harness after I lost sight of it and I didn't know it, I feel dumb but so thankful I am not pulling the carb bank. It purrs like a kitten. Now to finish the rest of the chrome and try out the new 6 degree triple tree's. Thanks everyone for all of the input.....Mike

Thats good to hear, Let us know how that 6* triple tree works out for you.

Tom