270 race tune findings

[ClutchMaster]

At 108 you losing a ton of efficiency being over 1:1 shift out

 

[ClutchMaster]

Yamaha clutches will not shift any further than .9 ratio no matter what you do, primary is bottomed out. Well I suppose you could have the clutches cut but it’s an efficiency thing, and will still be doggy above 1:1 shift.
Best bet is to go with gearing, your so overpowered at low speeds it’s sick. The only way you could ever utilize that gearing is with ice chisels on a lake.

 

[theewarrior]

What do you think of the 35/37 helix tho I have to decide to buy it

View attachment 137242
You fully shifted out. Need more gearing.

That's exactly what I thought when I had the chain case apart this week I asked the question, should I put the 22 gear in and everybody that replied told me it would be too high , darn now it's back together

 

[theewarrior]

I guess the chain case comes back apart again LOL

 

[ClutchMaster]

What do you think of the 35/37 helix tho I have to decide to buy it

That's exactly what I thought when I had the chain case apart this week I asked the question, should I put the 22 gear in and everybody that replied told me it would be too high , darn now it's back together

35/37 is a better combo with the TP orange second spring. Are you running stock weights?
With a 270 tune you will have absolutely no problem pulling those gears easily.

 

[Never Satisfied]

Yep, out of gear, this is the calculator I use and it's very accurate. That 3" pitch with 8 tooth drivers really slows this thing down.

speed at 1:1 102.44
105% 107.56
107% 109.61
110% 112.68
113% 115.76
115% 117.80
117% 119.85
120% 122.93

How fast do you want to go? 21/38 will get you into the low 120's. That alot for a big lug track. Not easy to swing that airdam around.

 

[fast n furious]

Yep, out of gear, this is the calculator I use and it's very accurate. That 3" pitch with 8 tooth drivers really slows this thing down.

speed at 1:1 102.44
105% 107.56
107% 109.61
110% 112.68
113% 115.76
115% 117.80
117% 119.85
120% 122.93

How fast do you want to go? 21/38 will get you into the low 120's. That alot for a big lug track. Not easy to swing that airdam around.

My 137 stock gears 21/41 hits 128 on power trail tune on perfect conditions

 

[ROCKERDAN]

My 137 stock gears 21/41 hits 128 on power trail tune on perfect conditions

he is talking bout 3" pitch track w/8 tooth drivers.

 

[fast n furious]

he is talking bout 3" pitch track w/8 tooth drivers.

My bad

 

[theewarrior]

Thanks I just think I'd like maybe a little bit more when the going is really good, so yes I think one tooth would be plenty ,, thanks again

 

[theewarrior]

Just curious anyone have a boost gauge on there 270 race tune?

 

[snowbeast]

My 137 stock gears 21/41 hits 128 on power trail tune on perfect conditions

Is that gps or speedo?

 

[snowbeast]

Just curious anyone have a boost gauge on there 270 race tune?

Those who have that tune,say its right at 17 psi on there dattalogger,for those of us who have the now old fashioned boost gauges they may read a couple high,so on your tune it may say 19 but it is really getting 17 so don't worry.

 

[theewarrior]

Those who have that tune,say its right at 17 psi on there dattalogger,for those of us who have the now old fashioned boost gauges they may read a couple high,so on your tune it may say 19 but it is really getting 17 so don't worry.

It's a new gauge Dynotune full digital

 

[snowbeast]

It's a new gauge Dynotune full digital

Sweet,i will have to check it out.