dyno 3

[C41Xracer]

with all the arguing over HMF's dyno #'s did any one go to there web site?i did and i feel a little better.The numbers for the yfz were 33.8 hp-22.4 tq stock, 38.8 hp-25.8 tq with slip on & 40.5 hp-27.4 tq with full exhaust. The trx 33.1 hp-25.7 tq stock ,34.5 hp-27.8 tq slip on only & 38 hp-28 tq full exhaust (sorry cant see last #'s real well on chart) I feel theses #'s are pretty acurate and the 1.4:1 compresion diffence would make up the 2 hp with the full on exhaust. Now what kind of #'s could we see with a K&N filter and aditional jetting changes.From what i get out of there web site all testing is done with the factory filter in place.If I'm worg any where inthis correctme please.

[VIC]

I hope your right.

[C41Xracer]

go check out the web site the full exhaust dyno page is very easy to miss its totally sepratefrom the slip on exhaust page.

[MIA450R]

I don't see where you're reading 38HP for the TRX with the full system...I read more like 36HP. I think you may have been reading the TQ curve for that #.

All the other #'s appear accurate, as long as that 1 YFZ450 dyno chart is read as: green/stock, red/pipe only, and blue/full system.

Dang, my 416 had numbers in this range.

HMF dude,
Could you kindly confirm all of the #'s--for the YFZ and TRX? Also, can you confirm all the airbox/air-filter/jetting mods to the YFZ and TRX for each of these tests?

[C41Xracer]

like I said correct me if I'm wrong.

[jdt]

I maybe wrong, but I think slapping an FCR carb on will put the HP ratings up! That will be one of the first things mine will have on it. (wish it came with one)

[450rboy]

Originally posted by C41Xracer
with all the arguing over HMF's dyno #'s did any one go to there web site?i did and i feel a little better.The numbers for the yfz were 33.8 hp-22.4 tq stock, 38.8 hp-25.8 tq with slip on & 40.5 hp-27.4 tq with full exhaust. The trx 33.1 hp-25.7 tq stock ,34.5 hp-27.8 tq slip on only & 38 hp-28 tq full exhaust (sorry cant see last #'s real well on chart) I feel theses #'s are pretty acurate and the 1.4:1 compresion diffence would make up the 2 hp with the full on exhaust. Now what kind of #'s could we see with a K&N filter and aditional jetting changes.From what i get out of there web site all testing is done with the factory filter in place.If I'm worg any where inthis correctme please.

i like what your saying

[MIA450R]

From what little info we have thusfar, it appears as though in bare-bones stock form, the TRX and YFZ have similar HP, with the TRX having more TQ. Super!


But...


It seems as though Honda meant the STOCK TRX to be at this (slightly lower than CRF450R) power level...due to the cam & carb choices. Conversely, Yamaha meant the YFZ to perform at YZ-F450 power levels, by having the same cam & carb as the YZ-F450. The high-power potential of the YFZ is realized simply by making exhaust/carb/airbox mods. Adding these mods to the TRX (again, according to HRD dynos) doesnt appear to pull much more power out of the TRX...because the internal HW was not designed to put out as much power as the CRF-450R. Honda set its own performance levels, and built the STOCK TRX450R to replace the TRX250R....not to beat the new high-performance level set by the YFZ450.


Thus...


I am guessing, that by going with the HRC kit, you are actually getting a cam (and other goodies) that is much closer to the performance levels of the CRF450R internals. In turn, an HRC-equipped TRX, and a YFZ WITH the cam 'mod' (advancing the exhaust cam 1-tooth to the same timing as the YZ-F450) and appropriate pipe/jetting will net 2 quads will fairly similar power output. But still, I think the modded YFZ will produce just slightly more ponies than an equally modded TRX...but not enought to give any major advantage in a race.


Make sence? Comments?

[linkcmd88]

Originally posted by MIA450R
From what little info we have thusfar, it appears as though in bare-bones stock form, the TRX and YFZ have similar HP, with the TRX having more TQ. Super!


But...


It seems as though Honda meant the STOCK TRX to be at this (slightly lower than CRF450R) power level...due to the cam & carb choices. Conversely, Yamaha meant the YFZ to perform at YZ-F450 power levels, by having the same cam & carb as the YZ-F450. The high-power potential of the YFZ is realized simply by making exhaust/carb/airbox mods. Adding these mods to the TRX (again, according to HRD dynos) doesnt appear to pull much more power out of the TRX...because the internal HW was not designed to put out as much power as the CRF-450R. Honda set its own performance levels, and built the STOCK TRX450R to replace the TRX250R....not to beat the new high-performance level set by the YFZ450.


Thus...


I am guessing, that by going with the HRC kit, you are actually getting a cam (and other goodies) that is much closer to the performance levels of the CRF450R internals. In turn, an HRC-equipped TRX, and a YFZ WITH the cam 'mod' (advancing the exhaust cam 1-tooth to the same timing as the YZ-F450) and appropriate pipe/jetting will net 2 quads will fairly similar power output. But still, I think the modded YFZ will produce just slightly more ponies than an equally modded TRX...but not enought to give any major advantage in a race.


Make sence? Comments?

ya that is what i have been thinking

[Maxx_Action]

You know...

something else that may enter into the dyno numbers is the choice of stock tires. I understand that those are the same tires that Yamaha used on the Raptor, and rejected for the YFZ because they didn't hook well enough. The reason they use "dyno tires" is they are almost slick and get all the power to the rollers on the dynoe, knobby tires are much worse where that is concerned, and if those aren't the greatest tires, that may expalin some of the deficit in HP. Just a thought...

Maxx