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Discussion Starter · #1 ·
Well I've had the bits in my shed now for 6-8 months so i thought I'd better use them.

K+N panel filter
.42 idle jets
118 mains
0.80mm alloy washers under the needles.

My airbox is looking a bit sad, splits on all the bolt holes and inserts etc, araldite and urethane holding it together [I'm definitely up for a new one], so I didn't mind butchering it.
I put two 1 1/4"=32mm holes in the r/h side in the same position as the std intake hole then I put a 1 3/4"=44mm on the underside in each flat spot both r/h and l/h. I then urethaned some screen door gauze over the holes to stop rocks and big stuff getting in.

I had to reset idle from 2000rpm back to a more normal 800-900rpm. Better breathing??

Riding it, I really can't say it is any different. It may be a bit more powerful, but it also has a slight flat spot at about 3500 in top gear and doesn't come out of it till 4000 [I could revise these figures with more testing]. But through the gears it feels smooth and progressive. I have dropped my 100km/h revs from 4000 to 3900, it may not be quite those figures, but it has definitely dropped. I didn't test top speed etc, but did buzz it to 150km/h and all was OK.
The .42 idle jets got rid of some of the cackle/popping when backing off, but not all of it, a gut feeling is about 50% effective, I was hoping for more like 75%-100%, but I don't know where to go with it from here, maybe 0.44's, but that is getting big.

I didn't go all out with huge main jets and swiss cheesing the airbox like some, I was after a more moderate approach with the result being moderate gains.

I have to take the bike on a 700km ride next weekend, I'll update and let people know my progress.

PS Has anybody else micro measured their washers under the needles? I'd be interested to see what their results have been.




[ This message was edited by: tridentt150v on 2007-01-27 19:59 ]
 

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On 2007-01-27 19:55, tridentt150v wrote:
I have dropped my 100km/h revs from 4000 to 3900, it may not be quite those figures, but it has definitely dropped.
Only changing the jets and air filter will have no effect at all on engine revs at any speed.

Engine revs at any particular speed is determined by the gear ratios.
The only way you will drop your revs is by changing the size of your front or rear sprockets.
 

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Discussion Starter · #3 ·
Thats what I thought too, but all else is the same, so I can't explain the change.
 

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Didnt put a new front tyre at the same time did you Tri?
 

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Discussion Starter · #5 ·
No, all else is the same. Tyres are several 1,000km old, chain, sprockets, clutch everything is the same, no wind assist [if anything a slight headwind].
 

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Discussion Starter · #6 ·
Well I've got to say that power is about the same until around 140-160km/h, then once your on the mains the power is almost nil. I got it to 170km/h and it was slow to get there. This indicates that the 118 mains are too small. Any suggestions for size?

Also I'd really appreciate it if somebody could measure their shims under the needle jets with a micrometer.
 

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I wouldn't say go bigger yet due to slow top end. Being rich will cause that also. Put on the throttle and as you reach the end of the hard pull, back off the gas a little and see if you get some pull back. This would indicate a rich condition and a smaller main jet would be your answer. Should do a plug read, run WOT for a few moments under load, then kill the bike and coast to a stop. Pull the plugs and see what you got for burn indications.
 

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Discussion Starter · #8 ·
Thanks for that, but I did the WOT test and the slight roll off roll on test at WOT but it made no difference. I could back off a bit and it didn't really do anything.

This leads me to believe that the set up is wrong, maybe my mains are too small. But I'll do some more testing before I decide.

BTW plug chops are almost a thing of the past given the fuel we have over here, I lament the demise of lead super, it was so easy to read the plug colour - because it had colour.
 

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Breathe in, breathe out, breathe in, breathe out... - Bush "MachineHead"

With a stock exhaust - you just wont get it. Punching the cans ain't gonna cut it either. Your engine simply isn't breathing enough...

To feel the full effect, you are going to need to go to a 3 into 1 aftermarket system, or a period Sprint / Trident / S3 exhaust system (The latter requires some mods to fit).
 

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Discussion Starter · #10 ·
Std pipes, megaphone type open mufflers.

The pipes seem big enough, and they have good lines etc so I would have thought they would breathe enough, the mufflers are basically a small steel baffle with a big hole through them, about 1" plus perforations in the baffle screen, and a 2 1/4" exit.

I can't see anything wrong with them, but I'm willing to listen.
 

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TBS carb' mod's
'00 TBS
  Posted: 2005-04-22 06:02 by johnyC
You know that scene in Doctor Strangelove when Slim Pickens is riding 'the bomb'? well that was me this morning testing my bike up the bypass.
"Yeeeeeehaaaaaaa, yeeeeehaaaaaa, ya f#ckin beauty!"

before: standard 2000 TBS with TBS-TOR's, jetting stock with #38 pilots set at 2 1/2 turns out, stock needles and stock #98 mains. went OK but a bit wheezy in the middle.

after: airbox opened out with a 2" X 1 1/2" oval cut on either side plus K&N filter fitted. #40 pilot jets at 2 turns out, stock needles raised with one copper washer fitted beneath each, #115 mains. NGK Iridium plugs fitted, type DPR8EIX-9. goes like the clappers, pulls like a tractor from idle all the way to the red, open the loud handle at 3500 in 4th and it goes rather than just thinking about it.
Thanks to Jimmy, Blaine and everyone else who pointed me the right way.
 

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Hey trident,
When my t'bird was overjetted by the morons at PS from new, I found that it ran perfectly up to 6000rpm & then power dropped dramatically, & immediately it reached 6G. Rolling back the throttle resumed 'normal service'. So it makes me think that perhaps in your situation it is possible you may have to go down rather than up.
Cat is here at the moment & commented "Tell him to get a fast action twistgrip..it solves all problems!" :-D

Regards
Cuppa
 

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Discussion Starter · #13 ·
Tell Cat to sell his harley......lol
 

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Discussion Starter · #14 ·
Better yet tell him to keep his harley and sell me his '69 T120R, its too good for him anyway :-D

Hows the numbers on those ESB badges going? Gorgy was the big time organiser but I don't have an order or a number to go on yet. The supplier said he would do more so waiting on you guys.
 

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Discussion Starter · #15 ·
What thickness are your copper washers? 0.5mm maybe?

On 2007-02-07 00:06, Wombat wrote:
TBS carb' mod's
'00 TBS
  Posted: 2005-04-22 06:02 by johnyC
You know that scene in Doctor Strangelove when Slim Pickens is riding 'the bomb'? well that was me this morning testing my bike up the bypass.
"Yeeeeeehaaaaaaa, yeeeeehaaaaaa, ya f#ckin beauty!"

before: standard 2000 TBS with TBS-TOR's, jetting stock with #38 pilots set at 2 1/2 turns out, stock needles and stock #98 mains. went OK but a bit wheezy in the middle.

after: airbox opened out with a 2" X 1 1/2" oval cut on either side plus K&N filter fitted. #40 pilot jets at 2 turns out, stock needles raised with one copper washer fitted beneath each, #115 mains. NGK Iridium plugs fitted, type DPR8EIX-9. goes like the clappers, pulls like a tractor from idle all the way to the red, open the loud handle at 3500 in 4th and it goes rather than just thinking about it.
Thanks to Jimmy, Blaine and everyone else who pointed me the right way.
 

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On 2007-02-07 04:13, tridentt150v wrote:
Better yet tell him to keep his harley and sell me his '69 T120R, its too good for him anyway :-D

Hows the numbers on those ESB badges going? Gorgy was the big time organiser but I don't have an order or a number to go on yet. The supplier said he would do more so waiting on you guys.
16 should do it D. Haven't spoken to Gorgy, so if, in the unlikely event of him remembering about it & contacting you, tell him he's a short arsed little bastard & that he should've got onto it quicker.

Cat reckons his 4 speed trident will piss all over your sick TBS when he's finished it! :-D

regards
Cuppa
 

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Discussion Starter · #17 ·
No surprises there, my T150V Trident is way quicker than the TBS, mind you its got an extra 100cc, ya gotta love them pushrod motors.
 

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On 2007-02-07 12:35, tridentt150v wrote:
No surprises there, my T150V Trident is way quicker than the TBS, mind you its got an extra 100cc, ya gotta love them pushrod motors.
I'll bet its a fair bit lighter too
 

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Discussion Starter · #19 ·
MMMMmmm I will have to check it out, but the Trident was always a heavy bike for its day, I can't quite remember [used to be able to quote it parrot fashion once] I think about the 430lb mark? But I'll check when next I'm home.

I think the only reason the TBS is slower though is because of the factory setup, which I'm now attempting to correct. The TB/TBS etc has untapped power just waiting to get out without even doing anything overly mechanical - just playing with airflow and carburation.

[ This message was edited by: tridentt150v on 2007-02-07 16:32 ]
 

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Trust me, the flow on the stock TBS pipe is inefficient. You'll notice a huge difference, and be able to run larger jets if you change it out.

There is a reason that the 70-85 hp motor exhaust looks like this:



and the 98 hp motor looks like this:



It just flows better that way...




[ This message was edited by: cafetbird on 2007-02-08 19:17 ]
 
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