Ported HJR Motor What Carbs?

[Strm Trpr]

I ride 80% Dunes and 20% trails.

 

Sea Level at Pismo up to 4500ft at Sand Mountain, NV.

 

I'm 5-10, 280 and ride pretty aggressive.

 

I run 20x10x10 Sand Skate II's that bought back in 1995 when low profile paddle tires were the shit...

 

I'm also running stock gearing.

 

I have T5's on the bike now with stock carbs, stock intakes, stock reed cages and reeds, pods w/outerwears and stock porting.

 

I talked with Kevin at HJR and he suggested a Hardcore MX Port for my type of riding and weight.

 

The cases will be port matched and the crankshaft will be trued and welded.

 

HJR Noss Machine Cool Head with a set of domes for both sea level and 4500ft.

 

Kevin suggested running the stock carbs w/pods and outerwears, stock intakes, stock cages w/Boysen Dual Stage Reeds, the T5's and +4 on the plate running pump 91 octane.

 

Kevin suggested against running the other stuff that I acquired over the years which are:

 

35mm Keihin PWK Air Strykers

 

K&N Pods w/Outerwears

 

Billet Intake w/Internal Cross-Over

 

VF3's

 

Kevin said that the 35mm set-up might have a lazy bottom-end for my size and type of riding.

 

My question to you guys is, "Will this HJR Hardcore MX Ported motor run better on the stock set-up or the 35mm set-up?

 

Keep in mind these are Air Strykers, so I'm not sure if they respond better than typical 35mm PWK's.

 

If the 35's are too big for my set-up then everything except the VF3's are for sale.

 

Let me know what you guys think.

Edited April 2, 2012 by Strm Trpr

[ClayAiken]

I would either stay stock carbs and jet. or maybe try to come across some 33 pwk. Kevin knows best for your setup go by what he says.

[Strm Trpr]

I would either stay stock carbs and jet. or maybe try to come across some 33 pwk. Kevin knows best for your setup go by what he says.

Yeah, I agree, Kevin does know best, that's why I'm asking you guys for your advice.

 

For a starting point, Kevin suggested the stock carbs w/340 mains, 27.5 pilots and the OE needles on the middle clip at Sea Level.

 

I was thinking about having the stock carbs modified by RB Designs http://www.rb-designs.com/banshee-carb.htm and selling off the 35mm stuff.

 

I wished Keihin made 31mm PWK's.

 

If the 35's are too big, then their for sale along with the matching billet intake and pods w/outerwears.

There's also 6 pairs of pilot jets and 6 pairs of main jets and a braided sst throttle cable.

$425 USPS Priority Flat Rate Shipping to the lower 48 with tracking and insurance.

Buyer pays paypal fees or sends money as "Gift".

 

Here's a pic of the set-up.

 

Edited April 2, 2012 by Strm Trpr

[ClayAiken]

Yeah, I agree, Kevin does know best, that's why I'm asking you guys for your advice.

 

For a starting point, Kevin suggested the stock carbs w/340 mains, 27.5 pilots and the OE needles on the middle clip at Sea Level.

 

I was thinking about having the stock carbs modified by RB Designs http://www.rb-designs.com/banshee-carb.htm and selling off the 35mm stuff.

 

I wished Keihin made 31mm PWK's.

 

If the 35's are too big, then their for sale along with the matching billet intake and pods w/outerwears.

There's also 6 pairs of pilot jets and 6 pairs of main jets and a braided sst throttle cable.

$425 USPS Priority Flat Rate Shipping to the lower 48 with tracking and insurance.

Buyer pays paypal fees or sends money as "Gift".

 

Here's a pic of the set-up.

I would call up Kevin again and see what he has to say about those. I would go with whatever he told me. I just noticed that you already had the 35's. I would maybe throw em on there jet it and see if u like it or not if u think your getting robbed of bottom end sell them.

Edited April 2, 2012 by Hyper

[Strm Trpr]

He said for my weight and Dune Riding he felt that the 35's might produce a bottom-end that would feel lazy.

 

He didn't really comment on the mid-range or top end.

[Strm Trpr]

Just got off the phone with Kevin.

 

He said the stockers are hard to beat with the MX Hardcore Port.

 

He's seen the exact set-up put down 65whp all day long on 91 octane and +4* on the plate and stock ignition.

 

He said the 35's might get a pony or two up top but the trade off would be a lazy bottom-end.

 

Ultimately he said try out the 35's and let him know...

 

If the 35mm set-up doesn't sell, then I'll try them out some day.

 

Honestly I'd rather sell them and put the money towards the motor build.

[MarineNYC]

I ran 35s on my hjr aggressive trail port and it was insane. No flat spots at all. But I would stick with 33pwks. They seem to be the best all around carb

[dave5.0]

Id ditch the 35s and maybe do some 28s. Mainly because they are easier to work on. I'm with most of these other guys that your gonna lose bottom end with those bigger carbs. It'll rip prob just not down low. Youll be clutching more.

[possum]

All depends what ur looking for and what kind od riding. Do u want it real snappy down low but lose topend. Or do u want a violent pull on top but lose bottomend snap. Or strong down low but still hard pull on top?. That will determine eveeything.. My bro is over 300 and im 200. He rides my drag port on 38's and it still flys.

[Strm Trpr]

All depends what ur looking for and what kind od riding. Do u want it real snappy down low but lose topend. Or do u want a violent pull on top but lose bottomend snap. Or strong down low but still hard pull on top? That will determine eveeything.. My bro is over 300 and im 200. He rides my drag port on 38's and it still flys.

Strong down low and still pull hard up top !

 

I want a powerband like this.

 

 

Here is what my banshee made on a dyno. hoping to break into the 70s with some more work.

make have the case port matched and improve the intake flow and maybe more timing.

also this is on pump gas.

mods are 370 trail port

cut head

vf2 reeds

+4 timing mod on stock plate

2-1 intake manifold with 38mm PWK A/S

FMF fatties with PC silencers

[Strm Trpr]

I ride mostly dunes, but I do trail ride and hit the occasional OHV park for a little Moto-X action.

I want a torquey motor hi 30's and around 65whp.

The dyno plot above has a wicked powerband.

2000rpms worth of 40ft•lbs would be epic.

[decon]

I run 35mm Pwk's on my HJR Dune Ported motor, but for your application I would run the 28mm Pwk's like Dave5.0 said. My uncle's banshee had the same motor as me except 28mm pwk's, his bike was a lot more snappy in the low end.

[possum]

If u ride where the rpm is a lil higher(right below the pipe. It will be more then tourqey. If speed is a lil more important then lugging power 35s will be good. I say try both and u can pick one. Sometimes u think u want a certain feel until u try something different and like it more.

[Strm Trpr]

I think I'm gonna send my stockers out to Ron Black for his carb mods.

http://www.rb-designs.com/banshee-carb.htm

 

If u ride where the rpm is a lil higher(right below the pipe. It will be more then tourqey. If speed is a lil more important then lugging power 35s will be good. I say try both and u can pick one. Sometimes u think u want a certain feel until u try something different and like it more.

I agree, well said.

If the 35's don't sell, I'll definitely try them out.

 

I wish Keihin made 31mm PWK's.

[SandSlingerOR]

I think you will like the 28's if you ran them.