Jardine Torque Fix (Gatorbuell)

[GW 04 XB12R]

i know this thread is old, but I have an xb12r with an xb9 header, and a jardine can. this was the way i bought it. would this help me at all? i feel like whoever owned it last knew their stuff, after all the little things i'm finding. my theory is the exhaust will be faster already due to the smaller headers, so idk if this is an issue. also, is the size of the jardine different from xb9 to xb12? thanks

Gary

 

[AudiXB12R]

I just skimmed this thread, So I apologize if this has been asked...But if you see better performance using a 2 .5" reduced to a 2", would it make sense to try even more dramatic reductions in size? For example, a 2.5" reducer to 1.5"? Would that work better?

 

[TerryS1980]

GW 04 XB12R - This mod is to help with the loss of low end torque. Is your bike lacking this?

AudiXB12 - The only way to prove it would be to dyno it with the 1.5" and then with the 2". If you go too small you might lose a noticable about of power on the top end.

 

[buelladdicted]

The inside diameter of 2'' header pipes is usually 1.75 ".many dyno tests of 1200 sportster and buell show this to be optimum when larger displacements arent envolved.the smaller diameter headers of xb9 are most likely an advantage for xb9 ,but not likely for xb12 as they could be restrictive.Also,the size of the final opening of an exaust does not need to exceed that of the header to achieve maximum flow and scavengeing and therefor maximum HP and torque.Usually the openings of the best performing sportster pipes,such as se slipons,pithon 3 have 1.75 id final openings.Also, its more likely the jardine pipe dynos better on xb9 due to its shorter tuned lenth which compliments the higher rpm range it runs in.

 

[RH12s]

i just did this mod to my xb12 and noticed a decent difference in power, but it did also make my bike quieter....which is kinda a good thing considering the jardine is almost too loud, though it sounds great. I put a 2in reducer to 1.5in then bent the smaller end down a little. I was having a problem around 4000rpm with a flat spot that seemed to dissapear after a tps reset and this mod. Id like to data log it and see where its really at though as i havent changed the maps yet(its an 08)

 

[buelladdicted]

Its an important feature for the collector of a 2 into 1 to reduce diameter so it increases exaust velocety,thats how in theory at least,it takes 2 exaust pulses to increase the negative pressure in the individual headers seperately.With this said,it would be an advantage to maintain the same diameter from your reducer all the way to the exit,as to not loose that velocety.So its just my opinion that that this mod should be a definate performance improvement .

 

[WULFGODSXB]

its an easy cheap and removable mod i think i'm going to give it a try when i repack mine

 

[xoptimizedrsx]

dont forget the washer on a stick. It's a very old drag pipe trick to get back pressure back.

I put it in a few pipes and even Voodoo has used it in his pipes with good results.

mike

Edit: fixed "washer"

 

[WULFGODSXB]

xopti would you put it in the front by header or at the end of the muffler for best result. i know the washer trick works well with drag pipes 1" or 2" from the end but with the jardine its not like running dragg pipes i dont think

 

[Crewdog]

I made an insert and mounted it in the end of the muffler and angled it away from the rear tire. I.D. is 1-5/8 inches. Most all of the decel pop is gone and got quite a bit of low end back. Not sure if mounting it at the headpipe will perform better but will give it a shot when time to repack. Crewdog

 

[WULFGODSXB]

made a couple washer sticks last night and started to play with them today got rid of all most all my decel poping didn't have time to warm it up and realy ride yet i'm going to reset tps warm it up and take it out i also put high floe air cleaner on so deffently have to reset tps

 

[RH12s]

i just changed my plugs a few days ago and noticed that im running quite lean. After noticing that i ordered the ebr ecm for the jardine pipe and am wondering if i should take this mod out of the pipe to get best performance out of the ecm or leave it in? im pretty certain that im lean around 4k but havent done any data logging to back that up

 

[AV8guy]

how do you make the washer sticks?

 

[RH12s]

so after installing my new ebr ecm, i was quite impressed with the performance of my bike with this mod. I just took the reducer out today to see what kind of difference it made, and found that i def did lose some torque....needless to say, Im putting the reducer back in tomorrow.

 

[Laroucheyves]

Awesome rite up! Thanks!!! +1 for it... Love the mod!!!

Cheers

 

[jasoncummings64]

this goes to gator AND browland, went to autozone today.. And from the looks of your part you posted a picture of, it's the 2 1/2 I.d to 2 1/4 OD, THERE's WAS ALSO A 2 1/2 I'd to 2"od with a steeper shoulder... I need to know which one to use, I bougt both, if I us the dofter shoulder I will bend the rim like you suggetsed, or do I use the steeper shoulder w/out making the bend!?because it's already to siza!? Or does the actual two stage make a difference?

 

[jasoncummings64]

hers the pic of the options.. so u see what i mean

 

[GatorBuell]

Go with the smaller one, I bent the end down on mine to reduce it even more. If they had the 2" OD reducer I would have bought that one and used it. The problem with the Jardine is its designed for a inline 4 that benefits from less pressure and more airflow. The vtwin needs some back pressure to build torque. Thats why the Jardine works better on the 9, higher revs more air flow. At least thats what I think but could be way off.

 

[jasoncummings64]

do i bend the smaller one too? or leave it as is.. and where do i buy a banjo fitting for my damn caliper? brembo

 

[GatorBuell]

I would try it with out bending it first and see how it feels.