Timing Adjustment

[Starkey]

Sorry guys couple of questions.

Running 4 cell mod at MK on a 12 double with first generation 3300's and a GT7.

Do I need to play around with the motor timing as I am experiencing run time problems and not overly fast down the straight.

The motor is set on 15 degrees I think advanced. Looking down on the endbell it is turned anti clockwise.

Should I also fork out for 2nd gen 3300's.

Finally what would be the ideal mpr, currently it is about 38.

Sorry for so many questions.

[Mark Stiles]

Your mpr will be the problem. I run a 12 double, with 5 deg of timing adjustment. I have second generation team orion 3300's (although about 8 months old, so past their best!). I run about 34 mpr, and just get the duration I need (I need new cells). Try a smaller pinion, and skim your comm / fit new brushes if you haven't already.

What springs are you running on the motor? I had 6oz./gold ones on mine on sunday. I find these give me a significant power increase over 7oz./blue springs.

Also check your speed controller settings, and make sure you're getting maximum power. I struggled for straight line speed on sunday, and realised today that I had my mrt speed controller on a low power setting. I changed it to maximum, and you could hear the difference in maximum rpms!

[MattW]

I think you're both undergeared. I ran a 12x1 at one national last year with Panasonic SMH 3000 cells, they were shot after a hard season. The gearing that i ran was somewhere in the region of 41mmpr. Timing would have been somewhere in the region of 12-14 deg and i was able to last fairly easily.

A good person to talk to may be Jason Butterfield, (It was he who advised me to run like that last year ;D) and as he races at MK.........

[Mark Stiles]

how is running a higher mpr going to give me better speed AND enable be to avoid dumping?! Is it because the motor will spend less time at maximum rpm's?! What spring/brush combo do you use?

[jason]

Hi Matt,

I run a 12x1 fantom with 2nd gen 3300s at about 18 degrees advance.
At MK I run 38-39 mm/rev depending on the layout and finished the A final yesterday with 450 mah left in the cells. At larger tracks Macc and Plymouth I've been at 43-44 mm/rev.
I'm sure Mr Rice will testify for the staight line speed of my car at the last couple of nationals.

Jason

[rice98w]

everyone trust! jasons car is seriously fast down the straight"!!! :o :o :o :o :o

i couldnt believe it when he said it was a 12... and not even his best one!!!! :o (his best had had one skim too many that morning!)

YOUZA!!!! :o

;D

[Mark Stiles]

I'll testify for it as well after sunday!

[Dave Treacy]

Jason,

Can you spend 30mins on Kyle & my motors on Saturday to help with the setting of timing etc.

Kyle is running a 14d and I'll have a 10d, both BRM's as you reckon the Fantom 12d is too tourqy for 1/12th

[mark barord]

What we need to recognise is that when Matt is talking about running 41mm/rev he is driving softly, ie moving the throttle stick slowly, using half power in the infield and then only using full power for the final third of the straight. Driving like this will enable you to go faster and last for longer. There are some 1/12th scale racers who will never use full power in the race but personally I like to use full power on the straight.
Driving like this takes some getting used to, it can take about 6 months to retrain your left thumb but you will glad that you did!

[rice98w]

a useful tool is on your KO tranny, the down timer.

set the timer for 7 mins... and up untill then, dont use full power at all, not even down straights.

then... when it goes BEEP, you can give it some.

not only will you last, but your car will naturally "feel" better, as your not thrashing it, and the voltage in your cells will be higher across the average discharge of your run. you will be more consistant too!

this is the style of 12th scale, 8 mins... its fantastic.

you only have to watch andy moore, dave spash... all the top lads, to see that thrashing it isnt the answer, infact, andy's car at plymouth looked slow, but he set TQ with it!

practice, practice, practice some more! :)

[Mark Stiles]

Thats my trouble, I'm used to driving mardave cars and 1/12th circuit on a very short, twisty track, so I'm in the habit of throttle jamming. I'll act upon your advice at the next mk meeting I'm at.

[MattW]

What Mark says is quite true, but that was motor/gearing that i used in pure despiration when i couldn't last with anything else at Wickham last year.

For info my usual starting point is a Fantom 10x3 geared at 37.5mmpr. Now running 2nd gen GP's. That said i think 2nd gen have a little less capacity (generally) than the earlier ones.

[Starkey]

Hi guys, your comments are interesting.

I have come to the conclusion that my set up may not be that far out, appart from getting some second gen 3300's.

Jason, I don't know if you saw the end of the B final, but I dumped with about 2 mins to go.

One other thing that I did notice when I got home (better late than never) was my throttle high point needed adjustment, which maybe another reason why I dumped i.e. just under half stick was full throttle.

I'm hoping this was the reason why I was finding it hard to control smooth exceleration (it that the right spelling)

[PDW]

Nigel (and everyone else) what Mark says is the clue to it all. And it happens to the best of them .....

At his first 1/12th Scale Worlds, Masami Hirosaka simply could not make his car last. Despite everything he was told, he didn't adopt the 'no-full-throttle' style. Eventually, Mike Reedy made him run a pinion two teeth down from most other members of the Reedy Team. That fixed it! Despite that, Masami-san's ability to hold speed in a corner and drive accurately won him IFMAR World Titles at 1/12th.

It really isn't the mpr that counts, it's the way you drive the car.

(Another tip worth trying is to pop a piece of rubber above the throttle stick giving about 2/3 movement before you touch the rubber. Drive on that, with a conscious push against the rubber on the straight, and in the last minute of the race)