Track day on standard NX4

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jpe70
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Re: Track day on standard NX4

Post by jpe70 » Tue Nov 26, 2019 8:52 pm

trixynut wrote:Gollum,

I did plenty of track days on my TRX all across the UK and loved them all and how the bike performed.

It put out about 90bhp with FCRs and a pipe, and had some minor suspension tuning so nothing too wild.

There was always some guy on a GSZXCBRRRR1000 who whizzed past on the straight, but thats not the point. I was there to have a good day, get the most out the bike and go as quick as I could to the max of my ability, not to race.

If you want to always be "winning" like Trump, spend £10k on a superbike and hope your skill level matches it.
Spot on, that! =D>

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Racer-unk
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Re: Track day on standard NX4

Post by Racer-unk » Thu Jan 09, 2020 10:27 am

the idea is ....NOT changing from the TRX.....The modern bikes I race against are ridden by old amateurs like myself.....true they damn fast on the straight and have better dynamics, but as long as i keep reasonably close on lap times I am happy.
The true opposition I race against are the GSXR750 and modern 650s etc
I have beaten the latest model ERs that are well tuned, but there is nothing in the lap times. Just get to turn 1 first.......and don't F-up along the line.
Everyone loves my bike, because it's the only one racing in the country and sounds so damn awesome.

True...suspension is always challenging.....I do everything myself normally and have made some mistakes...but learning is half the fun.
Carburation still not sorted, but it runs OK.

Sending my rear shock shim stack away to have the shim stack upgraded for my weight after my next track day.

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Re: Track day on standard NX4

Post by coxylaad » Thu Jan 23, 2020 10:31 am

Everyone loves my bike, because it's the only one racing in the country and sounds so damn awesome.
They do sound fantastic. I love my bike the way it is with the triple engine, and it does sound savage, but I dont think its sounds as good as the lump it replaced. theres something about it, perhaps its the fact that its a big twin that doesnt rev very high so you can really hear the pulses through the exhaust.

couple of flyby videos from back in the day(6 years ago!) - I am on the black 900, and my father in law is on the red one with FCRs

https://www.youtube.com/watch?v=4SPv64lMsHA
https://www.youtube.com/watch?v=o9mxCLo48xg
https://www.youtube.com/watch?v=sRnv8CbvBcw

happy days.

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Racer-unk
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Re: Track day on a not so standard NX4

Post by Racer-unk » Sun Jul 26, 2020 8:54 am

So...yesterday I swung my wobbly 55yr old legs over the TRX for the first time in 4 months. "Testing at the track" they call it.
It was actually a dangerous affair as I have done nothing but office work for 4 straight months and have zero racing fitness, or any form of fitness at all. I did however manage a few good laps particularly during my second session.
But due to the lack of fitness, twice I strayed off the racing line, once having a massive front wheel slide on the dirty part of a corner where a car had dumped some soil and stones on the track and the other just loss of concentration and not making a fast corner and having a long farming excursion.

Getting back to the facts:
First session I went out and in and out and in, to adjust the rebound on the front end after having fitted the Racetech fork springs and a thinner oil.
Happy-ish with the front, It showed the rear end to be the culprit particularly during shifting my weight on the bike and gear changes at speed whilst at a big lean angle.

Session two, I reduced the high and low speed compression quite a bit at the rear, came in once to speed up the rebound up front by two clicks and then had quite a good session.
Came in and saw the rear tyre was wearing better than I have seen in a long time and the bike was much better balanced between the front and the rear.

Session three, no changes, I went out and struggled with consistency and pace....came in and saw the rear was wearing in an undesirable manner. Well this could only be the rise in temp from session 2 to 3.

We skipped a session and now my muscles was cooling down and I was getting stiff everywhere. (well not everywhere, but I am sure you understand)
Nearly did not do session 4, but my curiosity dictated another venture out. Slightly reduced tyre pressure at the rear and the tyre started to clean up.

It was the longest slowest load up I have done...just knackered.

Lessons learnt.....don't be lazy, change the pressure during the day as needed. Get fitter somehow.

PS, the club is hosting a race day in 3 weeks time. We don't know if there will be bike racing, seeing they have to get the go-ahead from a hospital that will take trauma patients in this Covid times.
Believe me you don't want to go to a state hospital in Africa, particularly now. Apparently, the private hospitals might not necessarily give the club the go-ahead.
I WANT TO RACE!

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Re: Track day on standard NX4

Post by cobbadiggabuddyblooo » Sun Jul 26, 2020 3:52 pm

Wait till you wake up in the morning...
How are your quads feeling after a nights sleep???
laughter is the best medicine

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Re: Track day on standard NX4

Post by Racer-unk » Sat Aug 01, 2020 5:25 pm

yes...muscles knew all about it. Had another track session today...only went out three times and rode well, but still riding unfit.

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Re: Track day on standard NX4

Post by Racer-unk » Mon Jul 12, 2021 2:27 pm

what I have learned in the last bit....
set rear tyre when it is hot on the warmer (SC)
Pirelli is good in Summer, but try something else in winter.
YZF750R transforms the rear of the bike. 180 race tyres last longer.
You dont have friends on the track....but keep it clean and laugh together afterwards....
Rivalry is great fun......as long as there is respect.
I still love my TRX, but it has a hard time on the track with my weight

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Re: Track day on standard NX4

Post by Tarwetijger » Mon Jul 12, 2021 2:38 pm

Racer-unk wrote:what I have learned in the last bit....
8<
YZF750R transforms the rear of the bike. 180 race tyres last longer.
8<
I'll stick with 160:
Effect of wider rear wheel

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Re: Track day on standard NX4

Post by Racer-unk » Mon Jul 12, 2021 3:30 pm

do you know how silly a 160 looks in a YZF750R swinger? Yeah I know the cons. That is a little bit of weight gain,.... the big problem is my 105KG and heavy leathers.....

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Re: Track day on standard NX4

Post by Tarwetijger » Tue Jul 13, 2021 9:22 am

Racer-unk wrote:do you know how silly a 160 looks in a YZF750R swinger?
I thought you wanted to be as fast as possible :wink:

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Re: Track day on standard NX4

Post by spiritedride » Wed Jul 14, 2021 2:29 am

My experience with a wider rear confirms the point that it takes a whole lot more rider input and physical input to turn,the TRX is very agile with its standard tyre sizes (front &rear),wider section tyres only benefit is to reduce wheel spin on exit drive,with the power output of the TRX its 160 section tyre is all it needs , so why lessen it’s agility by fitting a wider rear.

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Re: Track day on standard NX4

Post by Racer-unk » Sun Aug 22, 2021 8:02 pm

experienced some scary shit on race day.....one right-hand kink does not require braking, but you close the throttle for a bit before accelerating again. this is in 4th gear and revs drop between 5000 and 6000 somewhere (got to concentrate on the apex) Recently I felt a brief hesitation when going through that corner....this weekend if I open the throttle too fast exiting that kink the motor would lose power instantly unsettling the bike a lot and then fire again and start pulling as normal.
No other place on the track does anything funny happen.. I just adapted to rolling on slower and avoided the issue, but losing a tiny bit of time. This is new and had not happened two months ago or before that. Fuel supply to carbs is good.
Accelerator pump works properly....FCR Carbs set as per Cobba's recommendation for standard-ish motor


other than that, I had a good race day, despite it only being quali and two heats. I am frustrated though, because I am getting better and my race craft is improving, but I am a second off my fast pace and two seconds away from my goal, ....just feels like I cant get there... Fiddled with cabs today,.... idling smoother now and lifted needle one notch to see how it affect the pulling of the motor. Sadly I might miss the next two race days, as I need to go stay in a different city for 6 weeks.
That means my chances of the club masters Championship is out of the window......just as I started beating my main competitor again to level the points.

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Re: Track day on standard NX4

Post by cobbadiggabuddyblooo » Mon Aug 23, 2021 12:43 pm

I know that 5 to 6000 point in higher gears Bernard...Try removing the top of the airbox with the FCR’s and you’ll smell how rich it gets especially in a higher gear. It’s even worse with the Akrapovic 2-1. The Over and Nojima 2-1-2 systems I have make life a lot easier in that spot with a gain of 3-5 hp at 5500 but robs me of 3-5 at peak hp. I even put a 220 valve shim in the accelerator pump Bowl to take some of the volume away As the pump has the longest duration set up for the trx. You can change the diaphragm to shorten duration and volume. Different motors will have different characteristics and why the various acc pump duration/volumes..
Be mindful winter is almost finished and if the days are warming this could be impacting too. Any other changes with exhaust system mate??? ( length of can or outlet diameter??
laughter is the best medicine

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Re: Track day on standard NX4

Post by Racer-unk » Mon Aug 23, 2021 6:04 pm

20mm ish longer exhaust pipe

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Re: Track day on standard NX4

Post by cobbadiggabuddyblooo » Tue Aug 24, 2021 10:01 am

Ditch the air filter and top of the air box all together Bernard So you just running the bottom section of the airbox with the 2 curved bellmouths. See if u you find an improvement
laughter is the best medicine

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