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Knock Light Causes

yamamarc

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Not my sled but worked on it. Guy is seeing the knock light alot like almost every hard pull on 240,290 tune. Is this normal? If so whats recommended? Boost is too small to read at those speeds on gauge. Reason I am asking is my buddy with a cat has almost same issue. Every single time we have raced that was his excuse the last two years. I didnt believe him but saw it myself last weekend indicated on gauge after we did some friendly racing. You guys with tunes always have to run Octane Boost? If so what brand and what amount?
No knock light here and i have done some pretty long pulls with 1500km so far on all tunes! (Sm 225 240 270)Maybe a vendor will hopefully chime in with there opinion!!!
Defective knock sensor?
 

Motorhead

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I believe it's under the intake housing.

Thanks. Looked it up online, it’s on electrical diagram 1.
Saw what it looks like, so next time I check my sled out (couple of days) I shall take a peek at it’s location. Just curious! $115 +
 

bhall80

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This is my sled. Just did some testing adding Lucas 6 oz per 10 gallons per what I read. 270 tune hit 107 on speedo loose snow in a shorter run did it 5 times . Max RPM was 9090 and no knock light! Prior to octane boost RPMs struggled to get above 8750 before knock light kicked in. Boost meter hit 16 I think but tough to see at that speed. So far seems the octane is the answer. I’ll be riding all weekend at TY giveaway so when safe will do some more testing.
 

cannondale27

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That begs the question. Are the Knock sensor tunes too sensitive? From what I saw they are violent when the knock is detected. Will almost throw you off sled from the cut in rpm. Having ridden many Yamaha products with knock protection you dont ever know its there and power cut is seemless and gradual when it does throw a light. Now rumor was it was not even activated stock tune. How can that be true? I thought same thing on Phazer. Ran 87 for almost a year before I saw the light one day after a fill up of obviously crummy gas. Was this really researched? Oem knock protection is probably very valuable and could easily be hidden deep in the coding. I have my doubts whether it wasnt there.
 

jonlafon1

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At 6k on eco tune from TD. I never even had a knock light! This was version 1 when things got going in the very beginning. I had one time where the sled did a hiccup and a slight backfire in 6k. I usually always added a few ounces of TORCO or Klotz. Talking to another member who I believe knows his stuff well when it comes to TD tunes. He basically said eco is never going knock. Just tuned to powertrail and will continue with a smidge of TORCO on fill ups. Riding Michigan mostly.
 

cannondale27

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At 6k on eco tune from TD. I never even had a knock light! This was version 1 when things got going in the very beginning. I had one time where the sled did a hiccup and a slight backfire in 6k. I usually always added a few ounces of TORCO or Klotz. Talking to another member who I believe knows his stuff well when it comes to TD tunes. He basically said eco is never going knock. Just tuned to powertrail and will continue with a smidge of TORCO on fill ups. Riding Michigan mostly.
Sure seems like fresh good gas and the Octane boost is needed. That sure isnt advertised though. That is the problem for someone who thinks they are getting a turnkey tune you dont even have to think about. More and more I find its a Bullshit claim. Cant blame anyone for wanting the rush a stocker is lacking though. Just glad the booster is working. Second guessing that whole build. Not a good feeling and Knapp took the brunt of my frustration earlier. We are good and a nice ditchbanging river run cooled me off!
 

snowbeast

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This is my sled. Just did some testing adding Lucas 6 oz per 10 gallons per what I read. 270 tune hit 107 on speedo loose snow in a shorter run did it 5 times . Max RPM was 9090 and no knock light! Prior to octane boost RPMs struggled to get above 8750 before knock light kicked in. Boost meter hit 16 I think but tough to see at that speed. So far seems the octane is the answer. I’ll be riding all weekend at TY giveaway so when safe will do some more testing.
What tune is producing your 16 lbs of boost?
 

bhall80

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What tune is producing your 16 lbs of boost?
270 Hurricane but like I said tough to see clearly on meter under acceleration so I may be off.
 

WVTurboLTX

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I'm running Max Spool 17 and the only time I have seen knock light so far is one time launching on antilag. I have had many full throttle pulls this week to 110 with no issues. Been filling up with either 93 or non ethanol 91. No octane boost.
 

jonlafon1

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Sure seems like fresh good gas and the Octane boost is needed. That sure isnt advertised though. That is the problem for someone who thinks they are getting a turnkey tune you dont even have to think about. More and more I find its a Bullshit claim. Cant blame anyone for wanting the rush a stocker is lacking though. Just glad the booster is working. Second guessing that whole build. Not a good feeling and Knapp took the brunt of my frustration earlier. We are good and a nice ditchbanging river run cooled me off!
Eco is going to run on shitty Michigan 87 fro what I was told.
 

STAIN

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I have a 1000 miles on my SMT Hurricane tune with 91-93 octane and never seen a knock light. I run 270 almost exclusively. Maybe your sensor is a little sensitive?
 

1nc 2000

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The poor fuel quality found at some gas stations in the UP comes from Wisconsin. I went down to 240 tune because I got tired of adding to the fuel and it still knocks on e in a while on 91 octane especially from holiday stations.
 

cannondale27

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These things are $ pits once into the big tunes. Thats what I think. I thank everyone for honest results both good and bad. So if knock sensor is the issue do you have to replace it or just remove and re torque it?
 

staggs65

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Sure seems like fresh good gas and the Octane boost is needed. That sure isnt advertised though. That is the problem for someone who thinks they are getting a turnkey tune you dont even have to think about. More and more I find its a Bullshit claim. Cant blame anyone for wanting the rush a stocker is lacking though. Just glad the booster is working. Second guessing that whole build. Not a good feeling and Knapp took the brunt of my frustration earlier. We are good and a nice ditchbanging river run cooled me off!
It's all about good fuel. If the fuel isn't what the tuner says is needed that's not really the tuners fault that's the fuel suppliers fault. I've never seen a knock on Hurricane 270 running either 91 or 93 here. But I've never really strung it out for all it's worth either.
 

cannondale27

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It's all about good fuel. If the fuel isn't what the tuner says is needed that's not really the tuners fault that's the fuel suppliers fault. I've never seen a knock on Hurricane 270 running either 91 or 93 here. But I've never really strung it out for all it's worth either.
No. Tunes should be done to a average or below average fuel to make a happy customer. Claiming 270 on Unicorn fuel is not right. If knock sensor is bad that is a good excuse and not Tuners fault. The cause of this if fuel is lack of In Field testing before release.
 


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