Popping on Decel - UPDATE AND NEW PROBLEM

[Nico]

I have done/added the following and now get popping on deceleration:

De-smog
K&N filter (with foam pre-filter)
Exhaust taken off for truck stack add on. re-installed with new crush gaskets
No re-jetting or pilot screw adjustments

Suggestions???

Nico

[Jack]

Vacuum leak.  Check remaining vacuum tubes.
Exhaust leak.  Check exhaust bolts and gaskets again.

[Ricky-D]

After doing all that it may be time to look at the carburetor synchronization.  A little mild popping although an annoyance is not a sign of anything wrong or out specification.  The exhaust modification is the primary culprit in that popping.

[Garland]

I had the same problem, took a while to figure out one of the rubber plugs that I capped the carbs with was cracked and leaking.

[bigvalkriefan]

Check the intake o rings.

[Steve K (IA)]

Usually, it means your exhaust is sucking air at the head.  Did you get all 6 of the old exhaust gaskets out?  Re-tighten the header nuts?  Just my thoughts.   Let us know what you found.

[Chrisj CMA]

When you change the header gaskets.....then torque the nuts, the gaskets only just begin to "Crush" they will continue to squish down.  Each time you get ready to ride, check them.  I had to tighten mine 5 or 6 times before they were all the way squished 

[borat]

I had a bit of exhaust noise coming from one side.  Found a loose stud nut. 

What type of wrench/adapters do you use to get at those stud nuts?  Some of them are nearly impossible to get at with a wrench or straight socket extension.  I managed to tighten down all but one which I couldn't get at but a couple others are only as tight as I could get with a small wrench on an unrealistic angle.  Suggestions will be appreciated. 

[Chrisj CMA]

I had a bit of exhaust noise coming from one side.  Found a loose stud nut. 

What type of wrench/adapters do you use to get at those stud nuts?  Some of them are nearly impossible to get at with a wrench or straight socket extension.  I managed to tighten down all but one which I couldn't get at but a couple others are only as tight as I could get with a small wrench on an unrealistic angle.  Suggestions will be appreciated. 

I use a small box wrench and that gets them easily to the required torque.  Its only 7 or 9 ftlbs as I recall.......I dont use a torque wrench just the small box wrench and I never tighten them "as tight as I could get them" that would be too tight.  They will break

[borat]

I had a bit of exhaust noise coming from one side.  Found a loose stud nut. 

What type of wrench/adapters do you use to get at those stud nuts?  Some of them are nearly impossible to get at with a wrench or straight socket extension.  I managed to tighten down all but one which I couldn't get at but a couple others are only as tight as I could get with a small wrench on an unrealistic angle.  Suggestions will be appreciated. 

I use a small box wrench and that gets them easily to the required torque.  Its only 7 or 9 ftlbs as I recall.......I dont use a torque wrench just the small box wrench and I never tighten them "as tight as I could get them" that would be too tight.  They will break

Was that a straight shaft box end?   I have one stud nut that I can't even get a small wrench on.  I'm thinking I might need a curved wrench to get at it or maybe a small 1/4" universal joint for a socket.

[Chrisj CMA]

Was that a straight shaft box end?   I have one stud nut that I can't even get a small wrench on.  I'm thinking I might need a curved wrench to get at it or maybe a small 1/4" universal joint for a socket.

My box wrenches have a slight angle to the heads, that may be why they work.....

[Steve K (IA)]

I use a combination box/open end wrench and a 1/4 drive ratchet with a 6" extension and a universal joint/swivel just below the socket.

[Ricky-D]

I had a bit of exhaust noise coming from one side.  Found a loose stud nut. 

What type of wrench/adapters do you use to get at those stud nuts?  Some of them are nearly impossible to get at with a wrench or straight socket extension.  I managed to tighten down all but one which I couldn't get at but a couple others are only as tight as I could get with a small wrench on an unrealistic angle.  Suggestions will be appreciated. 

Get more tools!

[Dag]

I have done/added the following and now get popping on deceleration:

De-smog
K&N filter (with foam pre-filter)
Exhaust taken off for truck stack add on. re-installed with new crush gaskets
No re-jetting or pilot screw adjustments

Suggestions???

Nico

I'm curious .... about the conclusion   

[Nico]

So far I have re-tightened the header nuts (a couple of which were loose), and have new vacuum caps and intake o-rings on order to replace the ones already on the bike. But thanks to the off and on rain we have been having (and the fact that the front fender is off the bike for paint repair due to my stupidity) I have not had a chance to ride yet to see if the header nuts were the culprit or if  I need to continue up the line of checks and fixes.

I will keep you posted on my progress...

Nick

[borat]

I had a bit of exhaust noise coming from one side.  Found a loose stud nut. 

What type of wrench/adapters do you use to get at those stud nuts?  Some of them are nearly impossible to get at with a wrench or straight socket extension.  I managed to tighten down all but one which I couldn't get at but a couple others are only as tight as I could get with a small wrench on an unrealistic angle.  Suggestions will be appreciated. 

Get more tools!

Wow!  Did you come up with that all by yourself? 

I have tons of tools.  Obviously, I'm short a certain few hence the question.  An appropriate answer would have been a recommendation for they type of tools I should buy rather than stating the obvious......

[Ricky-D]

I have no problem getting at all of the nuts with just a couple of wrenches and a socket with an extension. 

The wrenches are combination wrenches one short 6 point and one long 12 point. They both have slightly angled heads. The socket is a very small 6 point (1/4 drive) with an 8 inch extension. Three wrenches in all.

Thin skin you!

 I would have thought if you're doing any kind of work yourself on your bike, you'd at least have the fundamental tools the kind of which I have just enumerated.

Hammers, chisels and vice grips wont get it!

[borat]

Thin skinned?  Hardly.  A guy asks a legitimate question and get's a reply that wasn't worth the time it took to read it.  Why would you bother to reply with an answer like that?   It wasn't informative and hardly humourous. 

As far as tools go, I have tons of tools from torque wrenches to dial gauges to electronic calipers and pretty much everything one would need including a metric/imperial 1/4", 3/8" 1/2"  drive socket sets.  Several sets of combination wrenches....etc.   I have been working on motorcycles for many years.  In the last year I have rebuilt two 1970's Yamaha RDs from the ground up and have maintained numerous ATVs, motorcycles, outdoor power equipment, outboard motors, cars & trucks.  I have only owned the Valkyrie for a couple months and hadn't been able to begin to work on it unil the last few days.   So, being unfamiliar with the machine, I thought that possibly someone on this forum would be kind enough to guide me in selecting the best tools to get at the exhaust nuts.   

Your second reply was much more helpful.  However, 1/4" drive socket and extension will not allow me to get at a couple of the rear nuts.  I had thought that a 1/4" universal joint would be what I needed and I might even have one....somewhere.  Now that I know it is esssential, I'll have to see if I can find it.  If not, I'll be off to the hardware store.

Here's a couple pics of my red '76 RD400 and yellow '74 RD350 and '03 Valkyrie:
 

[chrise2469]

Here is my suggestion for the best tool for the exhaust nuts: the  10mm gearwrench.  Thats the wrench with the ratchet on one end and a open end on the other.  If you get the thin one it fits on every bolt no problem.  The ratchet has a 5 degree swing so there is lots of room to operate.


I just put the exhaust back on tonite and it works great.  It goes onto all the bolts even the hard to get middle rear.


If your really concerned about the torque, just torque one of the easy nuts and find out how much "umph" you need with the wrench.

Hope this helps you.

[Tundra]

Nico,
I would start looking at what you touched last. Definately check torque on header bolts, (7lbs.) starting in the middle and working out on each side. Recheck torque after next several rides. There is a good article explaining this in the "shop-talk" section of this board. You could be running a little leaner now due to the mods you stated. With that being said, if you did have any slight vacuum leak, it could be amplified now causing an even leaner condition, which can cause your popping.
  There are many other factors which can also cause this, although if your bike was fine BEFORE you touched it, start with what you touched. Then you can also check and replace your vacuum caps to your intakes, change these if you have not (their cheap). Tighten the rubber boots to your intakes (top and bottom) This could be loose, especially since you had the air box off to do your de-smog. As someone mentioned, intake runner o-rings. If it still pursits, is the airbox cover seated properly? I'm sure you will find the culprit in the header bolts or the intake boots if that's what you touched last. If you have or can get your hands on a pilot tool, you could check and adjust your pilots, might need to richen a bit with the de-smog and K&N filter.

[Airetime]

I have done/added the following and now get popping on deceleration:

De-smog
K&N filter (with foam pre-filter)
Exhaust taken off for truck stack add on. re-installed with new crush gaskets
No re-jetting or pilot screw adjustments

Suggestions???

Nico

Sometimes getting the correct fit when reinstalling the pipes is a hit and miss, some go back on easy, some not. Here is a step by step from Mark T that has helped alot of us over the years. Take a look and make sure that you torque the header nuts to 7 ft pounds, no more. Mark has a trick for that one. I found a flex driver at the local hardware store bargain box that has a max torque of 7 ft pounds so I use it exclusively for the Valk.

http://www.horseapple.com/Valkyrie/Valk_Products/M2W_Exhaust__System/R_R_Tips/r_r_tips.html

http://www.horseapple.com/Valkyrie/Valk_Products/M2W_Exhaust__System/R_R_Tips/torque.jpg

[borat]

The ratchet wrench looks like a pretty good solution.  I'll probably get one of them and a 1/4" universal joint for the socket set. 

Thanks for the guidance and going through the effort to post pics.  Much appreciated.

[PharmBoy]

I have had no problems with exhaust nuts since I bought a 10mm wobble joint socket (cheap at Sears & reasonable quality for the number of times it will be used).  It is in 1/4" and placed on a 6" extension connected to a 1/4" torque wrench set at 84 in/lbs(7ft/lbs).  The rear nut on #5 is the only one that I have to guess at the torque.  I have a little ground down end wrench (a cheap one) that usually gets the nod here...JTL   

[Tundra]

Nico, Did you isolate your cause of popping? Curious ???

[Nico]

Well, here is where we currently stand. As I mentioned before, I did find some header bolts that were loose. So I tightened them up. Yesterday I installed the new intake O-Rings and new Vacuum caps. I started the bike up and got a little popping when I blipped the throttle to warm it up. Since the front fender is off getting paint repair, I couldn't take it out for a full ride (up to speed), but riding around our subdivision, at slow speeds, I was still getting a lot of popping. After a couple of times getting up to about 35 mph on longer straightaways, it seemed to pop less after downshifting, but I don't think I can really judge until I get a good long ride in fully warmed up and at normal driving speeds.

Now here is a different problem all together, when I took of the middle intake on the left side (I believe it is #4), the cylinder was FULL of gas. And I don't know how that is possible, as I have just put on a belly tank and the fuel should only feed when pumped in from the belly tank. It shouldn't be able to "trickle in" through a bad petcock from the tank as it no longer feeds directly from the tank. I used a rag to soak up all the fuel from the cylinder and it started and ran fine. But after having to pull the engine once already to replace the starter gear teeth (to the tune of $800), now I am very paranoid about this gas find. What should I be looking at that might have caused this problem???

Nick

[Black Dog]

Now here is a different problem all together, when I took of the middle intake on the left side (I believe it is #4), the cylinder was FULL of gas. And I don't know how that is possible, as I have just put on a belly tank and the fuel should only feed when pumped in from the belly tank. It shouldn't be able to "trickle in" through a bad petcock from the tank as it no longer feeds directly from the tank. I used a rag to soak up all the fuel from the cylinder and it started and ran fine. But after having to pull the engine once already to replace the starter gear teeth (to the tune of $800), now I am very paranoid about this gas find. What should I be looking at that might have caused this problem???

You got good spark at that Cylinder?  I know a belly tank should prevent that...  Any raw gas, dripping from the exhaust, or smell while riding?

Black Dog

[Nico]

No gas from the exhaust, but I did get some from the tank vent hose yesterday....hhhmmmmmmm the plot thickens.....

[Master Blaster]

A good tool is the Craftsman 1/4 in drive, size 10 MM universal socket.  Not too pricy and you will find lots of uses for it besides the exhaust nuts.  Much better than a 10 MM socket and universal extension.

[R J]

Question, since I'm getting in here late in the game.

Have you had the exhaust headers off the engine?

If so, did you replace the crush gaskets?

IF NOT, drop em down and do it.....

Then if it still pops, come back and see us again.

[Nico]

R J

Yes and Yes

[ptgb]

First, holy crap! Make sure you check that #4 each time before you try to fire it up so you don't relive the nightmare! Until you figure out what is the problem.
 
Second, I would start a new thread about the "filled cylinder, even with belly tank dilemma". This thread has gotten long and now involves more than one problem.

Third, I can't even begin to imagine what could be causing a cylinder to fill up with fuel like that with a belly tank installed. The only thing I can think of; is did you let it sit for an extended period with the key on, but the motor not running. The fuel pump would be running... the petcock would have no vacuum, but with the petcock mods for the belly tank, could it let small amounts of fuel to get through with the pump running? I know that would be a long shot, but can't think of anything else.

At this point, I would buy some steaks and favorite beverages and see if anyone in the Chicagoland area has expertise, especially with lightly modded (desmog, etc) valks, to get a second opinion on this stuff.

Good luck...