Triumph Rat Motorcycle Forums banner
  • Hey everyone! Enter your ride HERE to be a part of September's Bike of the Month Challenge!
1 - 18 of 18 Posts

·
Registered
Joined
·
309 Posts
Discussion Starter · #1 ·
The Thruxton's next mod is possibly going to be the Air Box Removal.
I have looked at the usual suspects that supply them and they all seem to sell them for roughly the same price. Are they all pretty much the same or are some better then others??
Also is this mod really going to make a big difference. Currently I have the AI removed and after market pipes and I think it runs great as it is but if it can run better I am all for it. My Triumph mechanic reckon's it's the way to go and he's a pretty sound bloke.
 

·
Registered
Joined
·
316 Posts
I'd recommend doing it yourself and saving some money. With K&N filters, jets, etc... you could do it yourself for under $100. With Uni filters, jets, etc... you could do it around $50. That leaves you $200 or $250 that you can spend on other stuff for the bike!

By the way, people have been getting about 5hp and 6f/lb of torque to the wheel with the addition of the airbox elimination to the exhaust. I can't wait to try mine out, stupid winter.

[ This message was edited by: OldSkoolFool on 2007-01-18 19:43 ]
 

·
Registered
Joined
·
85 Posts
If your interested I have a pre-carved up air box for sale...
Figure $25 for the air box plus freight...

 

·
Registered
Joined
·
162 Posts
The directions can be found in a thread just do a search for kark (keef's airbox removal kit) It is definately worth it, I have no real way of mesuring but I would say it added more than 5 hp. I belive Jenk's puts it at 68 rwhp. My own 2 cents, it was draining to much fuel from the bowls, so I had to raise the float level to 16mm, still within spec but one mm up from the factory 17 to make it work. Running 138/42 with 1 shim and TOR's. If you do it, rebalance your carbs.
 

·
Registered
Joined
·
716 Posts
Before removing or cutting up your airbox you may want to do what I did...change exhaust pipes to something ANYTHING is better than stock mufflers...rejet to a 125 main jet AND PULL THE LEFT SIDE AIRBOX SNORKEL...I found this a BIG improvement and it is reversable if you want to go back to stock...I am sure you will not go back after you feel the difference in the way it runs...BUT do not pull the snorkel with out rejetting to a 125 main...
 

·
Registered
Joined
·
309 Posts
Discussion Starter · #8 ·
Thanks for all the info provided. I have decided to go for a Uni Air filter and pull the snorkel out for the time being and see how that goes.
Just wanting to know what combination of mains and pilot jets I should order. Please excuse my ignorance. Mechanical stuff is definitely not my strong point and I am somewhat clueless.
I already have had the AI removed and aftermarket pipes and I know the bike was re-jetted before i bought it but unsure of the jet size. Is there anyway I can tell what size the jets are, maybe I won't have to get bigger jets??

Thanks again folks.
 

·
Registered
Joined
·
176 Posts
Itcha, The jet size should be on the head of the jet. Although, I have seen some without. Don't forget to order a carburetor screw kit, if you don't already have it on.
Have fun.
 

·
Registered
Joined
·
309 Posts
Discussion Starter · #10 ·
I had a look at the Jenks Tuning Notes and was able to get the recommended jet sizes from there for the setup I want.

Cheers all
 

·
Registered
Joined
·
57 Posts
Itcha,

if you remove the snorkel make sure you fixate the K&N Filter somehow. I used a specially designed lid to avoid sucking in little birds :razz:



I used a 128 main jet.

I would also recommend to increase the size of the hole in the slide from 2.5 to 3 mm and shorten the spring a little.


Having all this done you'll think it's a different bike. Trust me!



Streetsailor
 

·
Registered
Joined
·
716 Posts
Sorry for the delay in my reply... YES there is a big difference in just pulling off the snorkel...BUT you can NOT just pull off the snorkel and feel a difference you need to rejet for the larger amount of air comming in with the snorkel removed. If you want to check me on this try running 125 main jets with the (snorkel IN palce) at wide open throttle...it will run fat/poorly at wide open throttle BUT pull that snorkel out and run it again at wide open and it will run clean and crisp up to top speed...someone asked how do you know what size jets they put in? The size is stamped on the bottom of the jet in tiny numbers you MIGHT be able to read them with a mirror and the bowls dropped but I couldn not and I can pretty much assure you they are NOT 125 jets if you only have pipes changed...because it would not run right...The 125 mains with the snorkel pulled works so well for me I will not make any other changes and you can easily reverse it back to stock ,,,you can get "Kehin" carb main jets at any honda shop for around $5.00 each...
 

·
Registered
Joined
·
799 Posts
What the hell is this contraption? - looks like something I may need...

On 2007-01-23 10:10, streetsailor wrote:
Itcha,

if you remove the snorkel make sure you fixate the K&N Filter somehow. I used a specially designed lid to avoid sucking in little birds :razz:



I used a 128 main jet.

I would also recommend to increase the size of the hole in the slide from 2.5 to 3 mm and shorten the spring a little.




Having all this done you'll think it's a different bike. Trust me!



Streetsailor
:huh:
 

·
Premium Member
Joined
·
292 Posts
I originally fitted a Uni-Filter, & NH belmouth with custom exhausts after removing the AI. Slide drilled to 3mm, 1 shim, stock pilots, 135 mains. Big improvement, 69 rwbhp. After completing my suspension & brake mods I felt the bike could handle more power safely and I fitted a NARK. Mains re jetted to 140 no other carb mods. 73 rwbhp and the bike really hauls to around 190 kph (118 mph) reaching 200kph (125mph) reasonably easy but then I'm bouncing on the rev limiter. I think this is the max the bike will do without resorting to TI's more comprehensive mods. My sense is that the bike will remain reliable and I assure you it's a pleasure to ride. My advice would be to save your money and go straight to the NARK. A bonus is the induction roar through the K & N's when you pin the throttle. You'll never get that with the air-box in place. And that's how a Triumph should sound!!
 
1 - 18 of 18 Posts
Top