[larryziehm]

Hello,

Can you overtighten the gaskets? I have a 2013 with Vance and Hines staggered pipes, which I love but have had that flat spot on the higher rpm's of first couple gears. So I got an EJK tuner and a Cobra powerflo. Issue was still there, but definitely not as bad. So I figured it was because of my laziness of not changing the exhaust gasket when I changed the pipes (I know, I know). So like many I went with the fel-pro gaskets (which are not like the crush gaskets from yamaha), took my pipes off and yeah evidence of exhaust leak, black soot looking on the bottom of one of the heads. So I changed them with the fel-pro (almost looks like layered cardboard material) and tightened the acorn nuts tight, rode it and it started off great. But I could smell the material almost burning, maybe cause it was hot --> is this normal? By the time I got done test riding it, my pipes were super hot, so I thought dang maybe I didn't tighten them enough. So sure enough the bolts tightened even more. Now I drive 1 mile and my pipes are crazy hot on a cold day. The bike backfires on decel, and has them flat spots. So I am thinking I crushed those fel-pro too darn much. Ideas, comments, criticize are welcomed. Is there a special trick to these darn gaskets? Should I use some kind of gasket filler/glue? Baffles are in, EJK with stage 1 mods preset. Thanks guys for reading this super long post, but I felt background info was important.

 

[1304cc]

When I installed my Dragsters, I felt it was worth the money to buy the OEM Yamaha gaskets. Why buy $500 pipes and then cheap out on gaskets? Others will say the Felpro are fine. I humbly disagree. You also want to tighten the acorn nuts gradually, switching from side to side to evenly distribute the pressure and ensure they seat properly.

If the EJK didn't solve your problem, and the bike ran fine before the mods, get some quality gaskets and an extra set of hands to help you get em snugged up nice and even.

Good luck.

 

[11Stryker]

You will want to tighten them evenly with a torque wrench to 14 ft. lbs. Then after each of 2 or 3 runs. recheck them with torque wrench. Pipes are supposed to be hot. That's how the heat gets dispursed from the heads. if pipes were loose- pipes would be cooler than normal and heads could possibly over heat.

 

[JesterAZ]

I just did mine, same set up as yours. When I saw the oem gaskets vs the cardboard felpro ones I was disappointed. I will get the OEM ones next change. Yes there was a smell on the first run, new gaskets seating in. It went away after a few miles. Dont over-tighten them, evenly torque 14lbs and re-check after a few runs. If you overtighten them, it'll flatten the gaskets and leak. You can also damage the heads. When its cool, if you wipe a rag around the heads it will be black, which means leak.

Your pipes running super hot so quickly and flat spots sounds like you're running too lean. Up the EJK settings an increment at a time (one setting makes a big difference) and test run it. Pop on hard decel is normal but there shouldnt be excessive popping. Another sign of lean conditions.

 

[larryziehm]

Thanks guys for the advice, ordered the stock yamaha gaskets today. It never occurred to me to use a torque wrench to 14lbs. And 11stryker great point about warmer pipes being better than the heads.

 

[DraEagWol]

hate to break it to you Larry..... but at the Stryker Rally down in Maggie Valley, we compared exhausts / intakes / & fi tuners....

The common denominator of those of us that have dead spots (hiccuping) while holding the throttle steady (cruising)..... is the V&H Twin Slash.

None of the Cobra swept bikes have that same amount of dead spots...
the difference is the Cobra's have a crossover... and the V&H's don't.

Which really suks, because the only solution now is to replace the pipes with something that does have a cross over (or has two O2 sensors) or just live & deal with it.

you may get lucky and with more adjustments.... minimize the problem enough for you to live with it... best of luck.

 

[11Stryker]

The Vance & Hines Big Radius 2 into 2 do have a crossover. Son has them on his bike and O2 sensor screws directly into crossover. The twin slash is another story. I have a set of the V&H Twin Slash coming that I bought and I plan on welding a crossover into them with a O2 bung. Will keep you guys posted how it works when I get to that point.

 

[larryziehm]

Wow that blows. Thanks for the replies guys. Gonna change my gaskets in the morning b/c I know I over-tightened the fel-pro ones I installed. Got the OEM ones and make sure I torque them to 14 lbs. I haven't the slightest idea what the crossover or extra bung is... So I'm gonna have to reaearch it a little. Worse case scenario I will get some other pipes and sell my Vance and Hines ones...

 

[JesterAZ]

I'm running these pipes with an EJK and have not had dead spots, hiccuping, or surging yet. You disconnect O2 sensor when using the EJK so that may be why.

 

[razz]

Man, I just ordered v&h slash, cobra intake and ejk tuner today and reading these comments made me doubt my decision. Thanks for your input :beer:

 

[larryziehm]

Many thanks for answering guys. Jester has been awesome with helping, thank you. Like Jester pointed out, the EJK tuner runs with O2 sensor disconnected, and after using Jester's settings and the new gaskets to spec I am happy with the results. The dead spot is almost non existant, EJKs suggested settings for my bike was still lean, but after the tweaks it's almost perfect. I think (could be wrong) that the crossover doesn't really apply to us because our fueel management is an open loop, rather than a closed one. Next mod is to find out where to get the 30tooth front pulley... You guys totally rock, and your help was much appreciated.

 

[Adrenaline Revolution]

The common denominator of those of us that have dead spots (hiccuping) while holding the throttle steady (cruising)..... is the V&H Twin Slash.

None of the Cobra swept bikes have that same amount of dead spots...
.

Hey DEW, Long time...

I have the Cobra Swept pipes and my bike was hiccuping like a cheap wino at cruising speeds BUT...
A fresh set of gaskets, torques right with a touch of ultra high temp sealant cured it COMPLETELY
It has not hiccuped once since I did this and it was the only change made.
That was over 700 miles ago.

 

[1304cc]

Does the lack of the cross over really cause the flat spots? I have cobra dragsters with no crossover, and no flat spots in acceleration.

 

[DraEagWol]

Well I don't know empirically.... but just standing around comparing notes of who has what at the rally... that was the process of elimination... So, maybe all the bikes with V&H twin slash - had faulty gaskets / leaks... or ???

but if i get a chance to change my exhaust - i am going to --- like the cobra swepts or 2-1 tri pro, or the freedom performance 2-1... *shrugs*...

 

[mikoloe]

Well I don't know empirically.... but just standing around comparing notes of who has what at the rally... that was the process of elimination... So, maybe all the bikes with V&H twin slash - had faulty gaskets / leaks... or ???

but if i get a chance to change my exhaust - i am going to --- like the cobra swepts or 2-1 tri pro, or the freedom performance 2-1... *shrugs*...

curb burners dude! common dew!

 

[DraEagWol]

eh? what? I'm already deaf enough as it is! lol - the wife couldn't stand those curb burners being that loud! LOL.... hmm... may just have to get her, her own bike after all... now.. where'd i put that lottery ticket!