Yet another jet question

[Ever-frost]

The whole OVER exhaust.

[cobbadiggabuddyblooo]

By yourself a wide band O2 sensor set up with gauge and sensor then place the bung at the rear of the collector on the Over exhaust.
A few of us on here run this set up and what you save in dyno time, well and truly covers the costs.($250-$300)
You get real time o2 readings any so will take into account the seasonal and geographical changes.
Do a quick dyno run as a starting reference point then Once you sort the fueling with you 02 sensor go and do your final run. Single dyno runs are cheap at $30. You can then make any changes you feel my be an advantage with your IGNITECH.

[Ever-frost]

That would be one possible solution.

Actually nowadays any workshops aren't interested to adjust carbs at dyno without O2 sensor been installed.

Not interested to install the gauge to "cockpit", but it can be easilly removed after the carbs have been adjusted.

[Overlord Neil]

Everyone got the Sir Monkey Spanker... right?

[cobbadiggabuddyblooo]

Yer I took it as a compliment coming just a monkey spanner pleb

[Ever-frost]

The spring is finally coming here in north. As I told before the TRX didnt run as well as I wanted.

At the winter I changed the clutch plates and springs, because of the last summer traffic jam driving.

Yesterday I changed the main jets from 148 to 144 and I repaired the filter box to original.

I really think that now TRX is pulling better at the high revs/full throttle. Maybe the 148 jets were too big for this setup.

[cobbadiggabuddyblooo]

Stick with the 2-1-2 Over exhaust and be mindful of you choose to go to a custom 2-1 system, this will only rob you of midrange power which is opposite to what you want due to the characteristics of the 270* crank and exhaust pulse from the 2-1 exhaust.
Try a 142.5 or a 140 main jet.
Your still too rich.
The TRX runs horribly rich from the factory and 2 or 3 jet sizes smaller is nothing unusual to get things into the 12-13:1 range.
The air density there will have a small impact on the main jet size but not by by 10 point size increase like you tried.

[Ever-frost]

Its strange that on the dynojet jet package they suggest to use 148 on better flowthing exhausts.

Of course the whole truth would come out with the oxygen sensor, but I think I'll stick with these 144 main jets for a while. Obviously the factory setup is on too rich without any mods.

I dont know will the K/n filter and ignitech unit make any difference with the OVER system.

[cobbadiggabuddyblooo]

Do a dyno run , that's the only way you'll find your answer.

[Racer-unk]

My shipment from 6 Sigma is missing in the post, but I receive my New needles, and little white covers tomorrow.
Anyway I stripped the carbs which were running really rich. They were really filthy and jets had a lot of additive/dirt "build-up" on them
I will try and remove pilot jets tonight and clean them.
Its crazy when you cant see what size the main jets are.

Somebody put 145 Starter/Main air jets in when the bike was dyno-ed about 8 yrs ago (I only did 2000km over the previous 4 yrs).....That's nearly double the standard size. How will this adversely affect Bottom,mid and top end?

[cobbadiggabuddyblooo]

Are you sure it wasn't running methanol??? A/F ratio is a lot richer for methanol.
Rich had 220main jets fitted in his TRX with TDMR's and he could only manage 60HP on the dyno.
Dropping the main jet close to std sorted his issue.

[Racer-unk]

No you mention it cobba, the bike was full of stickers when I got it and it had stickers on relating to a drag strip...It was Dyno-ed by a reputable person, but 8 years or so ago when the open pipe was fitted. I think I will take everything back to standard and work from there. thanks