17 or newer dynos with different pv springs?

I haven't found anything online.... ideally looking for hp/tq dynos on 17 or newer 300 with each of the different springs. Thanks!

14 minutes ago, flesh said:

I haven't found anything online.... ideally looking for hp/tq dynos on 17 or newer 300 with each of the different springs. Thanks!

Look on JD jetting website. Go to the pictures category. He did tons of dyno runs on the 17s. 

+1 on JD he has tons of graphs on the 17 with all three springs and various preload adjustments.

Looking at site now but it seems the dynos were done on an older model like a 13-14? If I'm right....  I guess it should still be directionally accurate?

Edited by flesh

Kreft did some

22 minutes ago, flesh said:

Looking at site now but it seems the dynos were done on an older model like a 13-14? If I'm right....  I guess it should still be directionally accurate?

He did the 17 with a Husky TE, should be the same as the xcw. I don't think there would be much difference.  They use the same cylinder, head and ignition. The only difference is the air box  and he did runs to disprove an open airbox helps.

Interesting, I found them thanks. Looks like very small gains from opening airbox.... maybe worth it to open it just a touch but much less than it appears many have on youtube?

I also emailed JD about a couple different dolly/spring configurations for different types of riding, interested to see what he says.... I could sorta get it from the dynos but wanted a max power configuration and then also a more linear config while maintaining as much power as possible for traction situations. 

8 hours ago, flesh said:

 Looks like very small gains from opening airbox....

If you ride at high altitudes, opening the box can be a winner. The Interwebs are full of hype and BS about jetting and air boxes.

You are looking for a unicorn. There is no configuration of any motor that has max power and linear power for low traction conditions. Max power is gonna be narrow and react like a light switch. To get bottom end torque and good response, you have to broaden the power band. There is no free lunch.

If you ride at high altitudes, opening the box can be a winner. The Interwebs are full of hype and BS about jetting and air boxes.
You are looking for a unicorn. There is no configuration of any motor that has max power and linear power for low traction conditions. Max power is gonna be narrow and react like a light switch. To get bottom end torque and good response, you have to broaden the power band. There is no free lunch.


Hell Pat, you seem like a good guy, meet me in Michigan and I'll buy you some tacos. Or a pizza. For once, there WILL be a free lunch!

Of course, depending on where you live, it'll cost something to get here.

Damn, there really IS no free lunch...

2 hours ago, -AC- said:

meet me in Michigan and I'll buy you some tacos. Or a pizza. For once, there WILL be a free lunch!

 

Deal, when does Spring get to Michigan? I flew in to Holland MI one Spring day a few years back, and they had like 10 inches of snow!

"I also emailed JD about a couple different dolly/spring configurations for different types of riding, interested to see what he says.... I could sorta get it from the dynos but wanted a max power configuration and then also a more linear config while maintaining as much power as possible for traction situations." 

Maybe this is just web banter but if I'm looking for a unicorn.... I must be looking for many unicorns? It's clear looking at the dyno's there there are more linear and less

linear configurations. 

Thanks for info on airbox, I do ride up to 10k feet. 

Deal, when does Spring get to Michigan? I flew in to Holland MI one Spring day a few years back, and they had like 10 inches of snow!

Spring in Michigan is a cruel mistress. We typically get a sunny, 50f weekend in late February, which gets you thinking you're close to breaking through winter's icy grip and getting out the bikes (dirt and road). Then March settles in with rainy/snowy temps in the low 30's. You make it through that thinking April HAS to get better, but nope, it's rainy/snowy with temps in the upper 30's. Finally May gets decent. Something to do with those big 'ol ponds that surround us...

I decided to go jarvis/walker style and try the green spring. Started at 1.5 turns in from full out and did 1/4 turn increments until there was no hit.... ended up at 

2.25 turns in from full out. BTW, this is nearly identical to waht jarvis and walker run. To each there own but now I have totally linear power. I am faster/better on single track and in techy stuff or long hills where throttle modulation is required as opposed to wot the whole time. The whole rev range is perfectly tractable and useable..... I;m often modulating through the whole rev range instead of switching gears staying low to mid....This is what makes me faster... I actually use the whole rev range more often i shift less.  I can be on the steepest longest hills and modulate from say 5k-9k as needed wo breaking traction... wo bogging...magic. Feels like my buddies 500 4t with a bit smaller rev range, a bit more off idle torque, but all the 2t nimble benefits. Love it. 

For hard enduro/single track, on a 300, I can;t see how anyone would find red or yellow better having tried them all now. my experience is red/yellow = wheelspin.... you can;t go faster than your tire can hook up! Perhaps if you;re a heavy guy.... which im not. Likely still the green would be best if heavier with less turns in from flush than me. 

I'm only pointing this out as a newb who up until trying this was convinced by the interwebs people that green was weak pointless etc. For me it;s money in every way. 

I decided to go jarvis/walker style and try the green spring. Started at 1.5 turns in from full out and did 1/4 turn increments until there was no hit.... ended up at 
2.25 turns in from full out. BTW, this is nearly identical to waht jarvis and walker run. To each there own but now I have totally linear power. I am faster/better on single track and in techy stuff or long hills where throttle modulation is required as opposed to wot the whole time. The whole rev range is perfectly tractable and useable..... I;m often modulating through the whole rev range instead of switching gears staying low to mid....This is what makes me faster... I actually use the whole rev range more often i shift less.  I can be on the steepest longest hills and modulate from say 5k-9k as needed wo breaking traction... wo bogging...magic. Feels like my buddies 500 4t with a bit smaller rev range, a bit more off idle torque, but all the 2t nimble benefits. Love it. 
For hard enduro/single track, on a 300, I can;t see how anyone would find red or yellow better having tried them all now. my experience is red/yellow = wheelspin.... you can;t go faster than your tire can hook up! Perhaps if you;re a heavy guy.... which im not. Likely still the green would be best if heavier with less turns in from flush than me. 
I'm only pointing this out as a newb who up until trying this was convinced by the interwebs people that green was weak pointless etc. For me it;s money in every way. 


You are setup almost exactly how I have my bike setup. Green spring, about 2 turns from flush, gnarly pipe. My bike has almost no hit at all, just usable, tractable power, and lots of it, everywhere in the rev range. It’s the perfect trail setup. If I wanted wheelspin and hard hitting power, I would have kept my yz250, it was great at breaking traction all the time.

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