Track day on standard NX4

Moderators: trixynut, Mincehead, dicky, phuk72, Jak, Kevtrx849

Post Reply
User avatar
Racer-unk
TRX-Enthusiast
Posts: 286
Joined: Fri Mar 03, 2017 5:28 am
Location: Port Elizabeth, South Africa

Re: Track day on standard NX4

Post by Racer-unk » Mon Oct 25, 2021 1:26 pm

Bitter sweet......Well due to my fatherly duties I have missed two Race days.
This past Saturday I was back in my home town and diced at the last minute to race.
I have been off pace lately, but 2 sec on average is depressing.

Anyway, armed with shit and other stuff off to the track I go.

I expected qualifying to be off pace as I am a bit rusty.
For Race One I put the old exhaust pipe back and head out. Get passed early by my opposition and he slow pulls away from me.....Until my gear linkage unscrews itself (my fault) and I am force to stop two laps early.
Thought the championship was lost there......

Race two, change the needles back where it needs to be and Immediately the bike feels a tad better, however after 5 laps the shit starts happening again and my nemesis gets onto my tail and passes me at the end of the straight...I cant keep up with him for a few laps, but towards the end of the race I am gaining again and pass him on the last lap (was too easy-----he thought it was the ZX10 guy coming to lap him on the last lap) Sweet revenge as I have stuff up on similar fashion before.

For race 3 we add more fuel and cut the long loop out of the fuel line......(maybe we losing pressure and experiencing fuel starvation at a point, but it still makes no sense....grasping at straws
Go out and the same issue on the warmup lap.....get away well and stay ahead for a few laps but then brilliantly out-braked a few laps later....from there the dice is on and I properly raced close to my competitor getting next to him a few times, although he always had the racing line to his advantage, ...I am waiting for a mistake. Then his GSXR motor expires in a big way with the pieces coming out of his exhaust hit my upper body as I switch from left to right behind him.

Bitter sweet .....I am now ahead in the championship......Wonder who's bike he will borrow for the final showdown....there are on or two quick ones available and in the master championship, you can ride anything. For Historic class he must comply to the rules. I am ahead by one point in both classes. There are one or two faster bikes and riders, but they have not pitched for all the races. Things have whittled down a bit with this co-vi-d crap and stupid rules.


So what is the bike doing....not as sharp/crisp as it was before.....and bogs down completely at 6000rpm in a particular righthand kink whilst going from closed to open throttle...although this is not the same every lap.

What I plan to do, .......new fuel filter, and reduce midrange timing advance by a degree or two. Going from 155 to a 150 Main jet and making bottom end 1/4 turn leaner.....

New

cobbadiggabuddyblooo
Site Sponsor
Posts: 6809
Joined: Thu Aug 28, 2008 9:19 am
Location: Brisbane,Australia

Re: Track day on standard NX4

Post by cobbadiggabuddyblooo » Wed Oct 27, 2021 6:07 am

Bit like Quartararo last weekend mate just didn’t quite hand you the championship yet like him tho.. I’ll be rooting for you mate at the finish line next round in spirit...
Try putting a valve shim in the acc pump bowl to decrease the capacity. Duration will still be the same just not as much fuel to draw on.
I recently replaced the tired old std coils with new aftermarket std coils and a good place to start... I’m now working at the WW2 warbirds museum so the bikes running on 100LL Avgas instead of a 10% toluene mix. I no longer have that big fueling smell when hard on the throttle in higher gears around the 4 to 6000rpm mark and can run more advance.
The 150 main might sort it out for you and the easiest option to start with.
laughter is the best medicine

User avatar
Racer-unk
TRX-Enthusiast
Posts: 286
Joined: Fri Mar 03, 2017 5:28 am
Location: Port Elizabeth, South Africa

Re: Track day on standard NX4

Post by Racer-unk » Tue Nov 02, 2021 10:06 am

Thanks Cobba

Post Reply