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Discussion Starter #1
So something I’ve struggled with for a while is gearing in the sand. The 1st gear on ratio on the kfx sucks.

I’m now running some 20x10x10 9 paddle haulers I got for cheap. The 22/11/8 6 paddles I had weren’t the best for all around duning.

I’m currently stock gearing. 14/38

When we go to sand mtn Nevada I can’t 2nd year launch to save my life. It’s at 4500 feet and bogs like crazy on 2nd gear launch. I get beat by basically stock raptor 700’s and piped yfz450’s right and left.

Then when we went to Oregon I raced a friends mostly stock raptor 660 and just barely kept up with him on the beach.

Click 5th gear and not much acceleration.

So next trip I’m thinking of either trying a 13 tooth front or 39 tooth rear.

The 13 tooth front will definitely take some speed away, But when we hill climb i don’t use 5th gear.

But I feel like the 39t won’t make much of a difference.

Maybe 13 tooth for high elevation hill climbs, 39 tooth rear for sea level dunes?

What do you guys think?
 

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Discussion Starter #2
So something I’ve struggled with for a while is gearing in the sand. The 1st gear on ratio on the kfx sucks.

I’m now running some 20x10x10 9 paddle haulers I got for cheap. The 22/11/8 6 paddles I had weren’t the best for all around duning.

I’m currently stock gearing. 14/38

When we go to sand mtn Nevada I can’t 2nd year launch to save my life. It’s at 4500 feet and bogs like crazy on 2nd gear launch. I get beat by basically stock raptor 700’s and piped yfz450’s right and left.

Then when we went to Oregon I raced a friends mostly stock raptor 660 and just barely kept up with him on the beach.

Click 5th gear and not much acceleration.

So next trip I’m thinking of either trying a 13 tooth front or 39 tooth rear.

The 13 tooth front will definitely take some speed away, But when we hill climb i don’t use 5th gear.

But I feel like the 39t won’t make much of a difference.

Maybe 13 tooth for high elevation hill climbs, 39 tooth rear for sea level dunes?

What do you guys think?
It’s been a year thought I’d update

picked up some new 21x12x8 6 paddle extremes.

swapped on the 13t front sprocket to see how I like it.

I’m also now running a shorty dasa, fci powerstack filter no box and some Sunoco 260 GT plus oxygenated fuel.

the new tires plus about 4-5hp more than Normal should make a nice difference.

ill report back on how I like it
 

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Question..Do you have control over your advance ignition timing, like with the Procom, PCV fuel + ignition or the Dynatek Fusion .....???

I'm asking because you might what to retard your ignition timing with a +3 stroker crank...?

Stock ECU is 39.5 degrees @ 6000 RPMs....A stroker crank will be over 41~43 degrees advance if I remember correctly..You might want to retard it to 35~37 degrees @ 6000 RPMs

Ignition Timing From 10° [email protected] 800 r/min (rpm)
to 39.5° [email protected] 000 r/min (rpm)
 

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So something I’ve struggled with for a while is gearing in the sand. The 1st gear on ratio on the kfx sucks.

I’m now running some 20x10x10 9 paddle haulers I got for cheap. The 22/11/8 6 paddles I had weren’t the best for all around duning.

I’m currently stock gearing. 14/38

When we go to sand mtn Nevada I can’t 2nd year launch to save my life. It’s at 4500 feet and bogs like crazy on 2nd gear launch. I get beat by basically stock raptor 700’s and piped yfz450’s right and left.

Then when we went to Oregon I raced a friends mostly stock raptor 660 and just barely kept up with him on the beach.

Click 5th gear and not much acceleration.

So next trip I’m thinking of either trying a 13 tooth front or 39 tooth rear.

The 13 tooth front will definitely take some speed away, But when we hill climb i don’t use 5th gear.

But I feel like the 39t won’t make much of a difference.

Maybe 13 tooth for high elevation hill climbs, 39 tooth rear for sea level dunes?

What do you guys think?
I had the same problem at pismo. Can’t launch in 2nd just bogs out. I launch decent in 1st but by the time I shift to 2nd the yfz boys are shifting to 3rd. I haven’t been to the dunes in 6 months. If I start racing again, I will buy 21x12x8 haulers. Why did you go with extremes?

I have a PCV + ignition but I never actually wired it to the dynatek ignition coil .

I Have yet to order parts for the rebuild. There was a motor on eBay $400 non running it’s must’ve sold. I could’ve used the cases. I will keep you guys updated on the rebuild.
 

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Discussion Starter #5
I had the same problem at pismo. Can’t launch in 2nd just bogs out. I launch decent in 1st but by the time I shift to 2nd the yfz boys are shifting to 3rd. I haven’t been to the dunes in 6 months. If I start racing again, I will buy 21x12x8 haulers. Why did you go with extremes?

I have a PCV + ignition but I never actually wired it to the dynatek ignition coil .

I Have yet to order parts for the rebuild. There was a motor on eBay $400 non running it’s must’ve sold. I could’ve used the cases. I will keep you guys updated on the rebuild.
yep I have the same issue.
takes forever to rev up in 2nd before the shift and by then I’m behind. Especially once we start going up hill.

I went with the extremes just because they hold up a little better due to the stiffer paddle

if I didn’t go with the 6 paddle extreme I would have gone the 7 paddle hauler.

the oxygenated fuel should help with the loss of power at elevation
 

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Discussion Starter #6
Question..Do you have control over your advance ignition timing, like with the Procom, PCV fuel + ignition or the Dynatek Fusion .....???

I'm asking because you might what to retard your ignition timing with a +3 stroker crank...?

Stock ECU is 39.5 degrees @ 6000 RPMs....A stroker crank will be over 41~43 degrees advance if I remember correctly..You might want to retard it to 35~37 degrees @ 6000 RPMs

Ignition Timing From 10° [email protected] 800 r/min (rpm)
to 39.5° [email protected] 000 r/min (rpm)
I’m running stock crank.

just shorty dasa, Fci no box with the new powerStack filter, and stage 2 cams
 

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I’m running stock crank.

just shorty dasa, Fci no box with the new powerStack filter, and stage 2 cams
Stroker in your avatar through me off..So If that's the case...

How was it with the stock gearing 14/38 with the 6 paddle before you went to the 9 paddle (2nd gear hole shot wise)...?

13/38 might be too low for dunes, great for putting over logs, around the woods & creeks...try the 14/39 first or Will you have tools to switch out your sprockets at the dunes...???

If your racing others like YFZ450, gearing lower 13/38 will slow you down..

You might want to add a +3 stroker crank for more torque to your motor on your next rebuild...??
 

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yep I have the same issue.
takes forever to rev up in 2nd before the shift and by then I’m behind. Especially once we start going up hill.

I went with the extremes just because they hold up a little better due to the stiffer paddle

if I didn’t go with the 6 paddle extreme I would have gone the 7 paddle hauler.

the oxygenated fuel should help with the loss of power at elevation
I found a set of skat trak 6 paddle streamed 20x11x9 I believe and a set of front Mohawks for only $150 all four. They need a good cleaning but I think it’s a good purchase. What do you guys think? These should hook up better than The 22x11x10 Hauler and much lighter up front than those itps I currently have. Still need to rebuild the bike but I can’t pass up this OfferUp deal
 
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