rpm sensor?

[kyleg]

so i phoned my dealership and talked to the mechanic to ask if the previous owner did anything to the gearing and they didnt tell me. i was concerned about the top end only being 158kph. i played dumb and asked what the top end on a xtx should be and he said 130-140kph i laughed and he asked me what i was getting and told him 158 and he said thats great (i have the hindle pcv and airbox mod and 1.75 track) i told him i put in a different primary spring to get my rpm up since it was only 8650 he said thats where i want it with my mods now its 8900ish (still same top end) and jumped up to 9200 few a second in powder then he said that there is a sensor and will tell them if the sled has ever went over 9000 rpm incase theres a problem with the motor that way yamaha has a reason to refuse warranty i guess has anyone else heard of this? also any suggestions to get a little higher top end? i was beating a friends 800 etec then i went on holidays and he put a clutch kit, exhaust, reeds and 1.5 track and now he beats me by 2 lengths. oh well at least i made him spend some money

 

[canoehead]

 

[kyleg]

funny canoe. was supposed to be just about the sensor but ya

 

[canoehead]

Well the part I don't get is (this happened to me) I was cruisin across the lake at a pretty healthy clip when I hit a patch of bare ice, well she hit the rev limiter, so what? I believe that's what it's for. I think your dealer is wearing his a$$ for a hat.

 

[Supa Dexta]

Some guys in the bike world beat their engines off the limiter every day.

http://www.youtube.com/watch?v=831E7N1dijA

Most computers nowadays will keep a record of such things, but they aren't gonna refuse it for a blip of high rpm, if it showed you were riding around for a season at 10k, or it blew when it hit 12k or something crazy, they may start getting picky.

 

[Beenba]

I call BS on this one. I can't believe Yamaha has incorporated an on board datalogger with memory that records and saves this info. It is very possible, but I'm not buying it - especially on a production sled. I will ask my dealer cause now I'm curious.

The rev limiter is what prevents the engine from over revving and causing damage, so there is no way to bypass that other than with a RB3 or PC5 or similar ECU modding hardware.

 

[Supa Dexta]

I dont mean a constant log at all, possibly just a couple data points of peak rpm and possibly sustained over revs.. Or perhaps nothing at all, but its not hard nowadays with everything being watched.. Hell it throws an engine light when the grip heater is unplugged.

 

[kyleg]

yeah i guess everyone wants to cover their butts.

 

[SRXSRULE2]

I work for Ford, we have the same deal. Have engine overspeed codes, especially important on diesel engines. I have seen the codes many times. Do I say anything? No. But if a customer bends a pushrod in a diesel engine and says "I don't know what happened it just started knocking" I usually can tell what they have been doing at the time of the issue.

I agree, Yamaha probably isn't going to refuse warranty because you hit the rev limiter a few times. Hell if they didn't want you messing with clutching they wouldn't offer optional weights and springs. If they see you are running past the limiter all the time, they may question it. If the engine is being run outside of its designed limits constantly, I could see why they would refuse a warranty repair.

 

[erosled]

The current crop of Yamaha sleds have no datalogging capability. All they can log is failure codes. The dealership person you spoke to may have been confusing sleds with the current Waverunners, which do log large amounts of operational data.