I am in the process of installing a yoshimura slip-on on my Nytro and have a question. I have heard that when installing a new exhaust sytem on the newer Yammis that the EFI will foul the plugs once. Is this true? Are the plugs difficult to change? I can access one of them pretty easily, but the other two are a different story. Is there anything that makes access easier without totally disassembling the sled? Any insight would be appreciated. TIA
Nytro Exhaust and Sparkplugs
- Thread starter Polarbear1049
- Start date
W
woodies
Guest
if you can change one you can change the others to because the tanks off!how you can get 1 without the tank off is a mystery!must have small hands!
I can get two out with a deep socket and extension without removing tank. I'm a girl so my hands are kinda small I guess.
ya you will probably foul the plugs as for getting to them your gonna have to take off the tank and everything. don;t fuss though with the panels all being 1/4 clips then only seat and tank its not that big of deal to get it apart and back togehter.
I'm pretty sure you can access the plugs from the left side, above the secondary clutch, without removing the tank.
Why would it foul the plugs once? I am also putting a pipe on and am very interested in this. If they foul what plugs do you replace them with, stock plugs from yami?
if you are running the oem fuel tank on the fx nytro, you can access all three plugs from the top left hand side of the sled. no i dont have small hands. LOL! it is a pain in the butt due to the plugwire/coil assy fitting very tight in the cyl hole for the sparkplug.
rotate the plug boots clockwise and counter clockwise while pulling upward on the boot carefully. the boot will pop out of the cyl hole with pacience and alittle time. use an extension with swivel, and a the smaller 5/8" std deep well sparkplug socket, and remove the plug. reinstall new plug, tighten and the add some dialectric grease to the inside of the boot, and then reinstall the plugwire/coil assy in the hole making sure it clicks on the plug and seals to the top of the cylinder well.
to make this very easy on you... mark each plug wire if they are not already marked (1,2,3) and leave the plug wires out till you get all three new plugs in. this will give you access to each of the plug hoes with no wires in the way. reinstall the plug wires from the right to the left (brake rotor side first, then the center, then the clutch side last)
if you are running the trail tank, you will need to tank the tank off to get to them. i cant see you ever fouling a plug with efi on a four stroke. never fouled one in a sport bike. you wont be changing these all the time like the two strokes, i can tell you that. some of the carbed 4 strokes would foul plugs (mostly in the warmer months) when guys would start them at 50-80 degrees when they were jetted from the factory to be safe well below zero. can you say holy over fueled cylinders batman? if you use common sense you will be fine. ski
rotate the plug boots clockwise and counter clockwise while pulling upward on the boot carefully. the boot will pop out of the cyl hole with pacience and alittle time. use an extension with swivel, and a the smaller 5/8" std deep well sparkplug socket, and remove the plug. reinstall new plug, tighten and the add some dialectric grease to the inside of the boot, and then reinstall the plugwire/coil assy in the hole making sure it clicks on the plug and seals to the top of the cylinder well.
to make this very easy on you... mark each plug wire if they are not already marked (1,2,3) and leave the plug wires out till you get all three new plugs in. this will give you access to each of the plug hoes with no wires in the way. reinstall the plug wires from the right to the left (brake rotor side first, then the center, then the clutch side last)
if you are running the trail tank, you will need to tank the tank off to get to them. i cant see you ever fouling a plug with efi on a four stroke. never fouled one in a sport bike. you wont be changing these all the time like the two strokes, i can tell you that. some of the carbed 4 strokes would foul plugs (mostly in the warmer months) when guys would start them at 50-80 degrees when they were jetted from the factory to be safe well below zero. can you say holy over fueled cylinders batman? if you use common sense you will be fine. ski
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I have not herd of this problem!
I installed a yosh on my MTX, and it runs and sounds sick!!!! It never fouled a plug yet.
I installed a yosh on my MTX, and it runs and sounds sick!!!! It never fouled a plug yet.
F
funjunkie
Member
To keep from fouling plugs let the sled warm up good before you start reving it up they run very cold plugs and need to get some heat in them first and do not shut it of right after reving it up let it run for a bite then shut it of. It just takes longer to make cyl heat with the higher flow muffler less back presure.
Went out for about 4 hours today with the new yosh rs5.Had one little high rpm stumble early in the ride but that was it.no plug problems.Sounds sweet
Thanks for the help guys. Yoshi is installed and sled seems to run fine. Sounds great too. I went ahead and pulled the plugs and then reinstalled them just to see if it can be done without removing the tank. It can, just takes some patience Plugs look good, I should be fine. I guess the real test will come when we finally get some snow around here.
Plugs look good, I should be fine. I guess the real test will come when we finally get some snow around here.Just installed new exhaust hope i dont have that problem. Good info for the future. I spoke with my yamaha machanic and he said the fuel injected sleds are not as bad as the carberated ones like the rx1 but let them warmup good.
Ran mine pretty much all last season with the Yosh Ti RS5 and not a single issue in over 3300 kms. I just swapped out the stock plugs a few days ago to the 10ek's, looking for a couple more hp. Stock plugs were golden brown when I removed them, and the sled fired right up with the 10's installed. Next is the K&N filter kit, should put me close to 150 hp.
The 10ek plugs are a colder burning plug, supposed to yield close to 2 hp in Yamaha 4stroke sleds. I actually heard of this mod many years ago where guys were installing them in their R1 sportbikes.
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