Triumphrat

SLOBonnie

So, I'm curious whether anyone has dyno'd the same bonnie (thrux included) with the following two different set-ups:

<u>Set-up #1</u> - aftermarket airbox filter (K&N, Uni, etc.), velocity stack (Bellmouth, Jenks, Polaris, etc.), restrictor plate removed, properly rejetted and freer flowing cans
<u>Set-up #2</u> - ABox removed (or chopped), pod filters (K&N, Uni, etc.), properly rejetted and freer flowing cans.

If so, does anyone know the RWHP & torque results? Was one set up significantly different? Also, that would seem to be a nice article to see on Rat.Net Wiki.

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BIR#171 / NTBF#155
'07 black (checkered) thruxton
(Mods: SB Sport Dominators, -ABox, 145/42 jets, 1 shim, 2 1/2 turns, -AI, Hyde steering damper, Works Street Trackers, Pirelli Sport Demons, Monza cap, Napoleon bar end mirrors, heritage badges)

1409

I only have step 2!!!

2004, 790cc Bonnie, no air box, K&N pods, 42 pilots, Thruxton needles, 150 mains, D&D cans.. This dyno run was 2000 feet above sea level, the chain was clean and lubed, 38psi in the rear tire...



[ This message was edited by: 04blackbonnie on 2007-06-04 17:53 ]

REVOLT

Option #2...

ARK, 135/42, Tear-Drop exhaust (straight thru)...
Ran 62.45hp at the wheel...I know I could get more HP with my new K&N cones...much larger than the Grey Cones that came with the ARK...and the bike pull harder and longer with the new filters...I'll be checking here after the next oil change.

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The Bonnie Situation...

meatwagon

option #1 except 'restrictor' plate still in

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Get it on,get it up,keep the beat
and RIDE WITH ZEKE
.................................................. .....
BIR #132
TonUp Club San Diego

Bonnie1000th

Hey Rich: How are you Mate?
I had the option #2 donned back in October 05 on a 790 motor , it did 65.9 RWHP, 49.9 RWTQ and perfect 13's A/F ratio, with 42 pilots,155 mains and 2 shims under the needles.
I'll scan it tomorrow at the office and post it.
I hope this can help.

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Tooo many mods!
1087
T100 Lucifer Orange bonneville.

http://www.triumphrat.net/photogallery/v/member/album788/album1500/aas.jpg.html

Shorty

SLOBonnie...I've had different results on the 4 or so Dyno Runs I had performed on my "02" with the 790 motor.
1st set up was (and I'm trying to remember) 140 Mains, 42 pilots , thrux needle with 1 shim, slides drilled, unifilter, restrictor removed and polaris belmouth. Sprint pipes and baffle. Max wheel Hp was about 58 and max torque was 48 ft lbs. Bike was running rich in the 10.0 to 12.2 range.

2nd set up was airbox removed and replaced with the NARK and the supplied 150 Main jet. I had also installed a BC igniter module to increase the rev limit. Everything else remained the same. Hp and torque specs were almost identical and the only gains I saw was in the speed vs. elapsed time data. My AF ratio was worst and running richer in the 9.2 to 11.3 range (but that's probably because the 150 Main was not the correct jet to use with the thrux needles...I have since dropped down to a 135 and waiting to get another run scheduled).

Bottom line , in my opinion, as far as air flow was concerned I saw no significant improvements with a modified free flowing airbox opposed to the NARK with the seperate K&N air filters. However it seemed to have made a tremendous difference in how much faster the bike gets up to speed ( 100.2 mph dyno reading in 13.9 sec with the modified airbox vs. 100.2 mph in 12.6 sec with the NARK / BC igniter addition...both by the way at 7300 RPM). I kinda wish that I would have got a run done with just the airflow modification and without the igniter for a fairer comparison, but I had too many toys to install and I was anticipating a big change

The extended RPM capabilities with the BC igniter gave my bike a 110.3 mph at an elapsed time of 16.8 sec . You can see that there's still room to play with (speed vs, time is irrelevant to me and my style of riding) but it appears that maybe 60 hp at the wheel and about 50 ft.lbs of torque is what we're going to get out of the 790 Bonnies unless you big-bore them and change the carbs.

Honestly in my opinion I think that a good setup with a free flowing airbox and filter combination is probably just as good as no airbox with the seperate filters. You have to decide whether the cost is worth the minimal benefits. By the way, all my runs were done by the same Technician (who was a well known flat track racer in the 70's and has tuned many bikes...I trust his opinions) with the same Dyno.

Shorty

PS: Sorry, I just realized that I addressed this feedback to the wrong person...it should have been to SLOBonnie

[ This message was edited by: Shorty on 2007-06-08 12:06 ]

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Different Strokes, for different folks.

2002 Red & Silver Bonneville
1972 Honda CL450 Scrambler
http://i22.photobucket.com/albums/b3...Bonneville.jpg
http://i22.photobucket.com/albums/b3...4/e0d93963.jpg

Bonnie1000th

Here it is.






[img][/IMG]

[img][/IMG]

__________________
Tooo many mods!
1087
T100 Lucifer Orange bonneville.

http://www.triumphrat.net/photogallery/v/member/album788/album1500/aas.jpg.html

Bonnie1000th

Rich here is the one with TQ and HP



790 dyno


790dyno

__________________
Tooo many mods!
1087
T100 Lucifer Orange bonneville.

http://www.triumphrat.net/photogallery/v/member/album788/album1500/aas.jpg.html

keef

Interesting. It's always good to see dyno figures for the mods we make to our bikes.

I'm 'way ahead of you. :razz:
If you look in the bottom right corner of the Twin Mod Links wiki page you'll see a link to the Twin Tweak Links wiki page. As well as having links to general mainenance topics, his has several links to dyno print-outs for many of the twins (I've also refered to a couple on this thread).

In fact, here's links to both...
Tweaks Page
Mods Page

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