Triumphrat

Grunt

Hey guys,
I took my 05 model Thruxton to the willowbank drag strip test 'n' tune last saturday.
My best result was a 12.698 second run with a 60' of 1.895 seconds and top speed of 168km \ 104mph.

Only basic mods to the bike so far:
AIRK
ARK
Madas pipes
17t front sprocket
re-jet 145's , 42's and 1 shim.

I managed to give a guy on a GSXr 600 a bit of grief with my nose in front up to about the 1/8 mark , then he left me behind to finish half a second in front.

The run against the GSXr 600 has got me craving for more go!

I'm tageting getting into the 11 second bracket to hasle the 600cc sports bikes.

I know gaining 1 second over the 1/4 mile isn't easy, especially with a limited budget.

I know that practice with launching from the start line is a big part of it, my best reaction time was 0.185 of a second.

Any sugestions on the next bang for buck mod to help with run times will be appreciated.

Dave2001

This might whet your appetite! - http://www.stabbarps-auto.com/welcome.html

Grunt

Very , very nice.
I have a mate who's pushing me to turbo my thruxton also.
I't just out of my price range at the moment.
Though i am considering it.

I'm thinking smaller at the moment.
Say, getting the cdi re-mapped and a set of race carbs then cam/headwork.
and maybe some laughing gas.

Varna2Win

Wow, I'd say that was pretty impressive run with those mods. I don't think my scrambler will even do 104 mph & I have basically the same mods as you. I really kick myself for not getting a 360 degree motor. I got suckered in by the looks of the scrambler in 06. I'd say next mods when you have the cash FCR carbs a lot of fellows in here will tell you not to waste your money on the CR'S & Hotter cams Also Pieman does some neat ignition mods for a fair price. When you get the money bore the sucker out. I think Mikeinva is one of the most knowledgeable guys in here when it comes to that - even thow he thinks I'm a dumbass . I do know that 1 mod compliments another when building engines-I think maybe Mike might agree with me on that. Good luck I should bought a thruxton.

Thruxboy

Most who go to the strip and run their motorcycle think its faster than it is. You sure don't fit that paradigm. Those are the best nos. I have ever seen for one of these bikes with the level of mods you have performed. GXRers will normally toast even a heavily modded bonnie. Best I would think you could do at that tune is low 13's with a tailwind.
Three things come to mind:
1. You are light
2. You are a fantastic rider.
3. Your bike is an absolute freak for the changes you have made.

Nos. don't lie.
Congrats.

mikeinva

thats great et for what mods you have done.I agree with varna on carbs as being your next mod .By the way I dont think varna is a dumb ass lol.
By the time you ran sounds like you know what you are doing.These bikes are kinda hard to launch sounds like you got it figured .They do get harder to ride the more hp you get them making.Some other things to do later are better cams ,a big valve head and a big bore and or stroker.Done right you can get over 100 hp at the rear wheel.

__________________
Why do I feel young on my bike

Gob-ny-geay

Budget things might be:

• Lose weight (you, and the bike!). Remove anything and everything you can off of the bike for the run. Practice your "crouch". Fenders, Speedometer, lights, etc?
• Aerodynamics - A Fairing? Small windscreen? Maybe on Ebay?
• Side-Gap the spark plugs.
• Only for the 1/4 mile run - pull the airfilters off and run Velocity Stacks (Mikuni's) - re-jet obviously beforehand.
• Tire air pressure? Add a few (5?) PSI to the front? Maybe lose 2 PSI from the rear? Again, only for the run.

Other than that, budget-wise, I would suggest getting the cylinder heads done (for highest air velocity and efficient cylinder filling capability) coupled with a three angle, blended valve seat, might be the next logical move. This won't break the bank. Don't know what you consider "Budget".

Note that building a bike for the dragstrip is a whole lot different than building a road-race bike, so bear that in mind.

I assume this would be a street/strip bike, so "streetability" needs to be considered as well when performing the various suggested mods. Most of the above you could re-install/reconfigure in less than a hour or so?

Yet another "Dumb-Ass" (and proud of it!),

Bob

Grunt

Thanks for the compliments guys.

I had headed to the track hoping that it'd be in the mid/high 11 second area.

With the 17 tooth front sprocket i was just off red line in 4th gear at the finish line, hitting the limiter just after the line.

The bike is in stock street trim at the moment, i will be looking at losing some weight off the bike (not myself I'm only 80kg/176lb ringing wet and 6'3" tall).

I managed to lift the front wheel on one take off which scared the crap out of me cause i wasn't expecting it and my chin was on the tank ready for take off, i also found it hard to get the front back down again with the throttle WFO. That run was a 13sec. flat.
My first ever wheelie on the Thruxton too.

I'll definately be looking at those FCR carbs and a pieman ignition map next.
Followed by some head work.


The other bike is a mate on a 250cc yamaha virago playing around.

henrys

Mid 12's without even cracking the motor open is really impressive. I bet 11's will be easy with some internal work.

Aussiematt

You'll want to throw on a set of green clutch springs to help your launches.

You'll do better once the temp cools and the air density is up

I used to go to Willowbank drags as a young bloke when I lived in Toowoomba. Some great memories....

__________________
2004 Thrux, FCR39's, Uni filter, 813 cams, Works shocks, Ricor valves, progressive springs, Pieman ignitor, green springs, GT501s, Beringer caliper, predators, damper, fork brace, Corbin gunfighter, custom tinware, lowered instruments, JMC swingarm