GT12 Help..

[Martin.s]

[QUOTE=mark christopher;921421]Pointless, use one or other, if you want stiffer damping use stiffer oil.[/Q

Ummm....and if you don't have stiffer oil available? Really just wondering why people don't try things that are a little more out of the box....if no one has EVER tried how does anyone know what effects it could have either positive or negative....

[SlowOne]

Originally Posted by shinytopman

Question for Slowone......

Any advice as to the timing sweet spot on the Hirosaka 13.5t?

Have just bought one and wanted a rough starting point

currently running 66t spur, 31 pinion, and new JFT in a zen sorry dont know the Diam. approx 48mm i think.

Thanks in advance.

Shiny.

Shiney, try 38 degrees. I have run to 40 degrees, but prefer that smidge less. Rollout is 66 to 68 mmpr depending on track shape. Tighter track, lower number. If your tyres are 48mm dia then 68 is a 30T pinion and 66 is a 29 - roughly! Mine are 45 so its 31 for the lower number and 32 for the higher one.

Ratio depends mostly in how much speed you carry in the corners and your driving style. If you rarely let fully off the throttle and can carry a lot of speed, the higher numbers will work. If the track is tight, or you are an off/on to roll the turn/full on the way out sort of driver, the the lower ratio will help.

Car should be flat about half way down the straight depending on the exit speed from the last corner. I like the motor a lot as it doesn't fade much and has strong torque even at that level of timing. HTH

Originally Posted by jimjav

Morning,

Yesterday I was preparing the body for my zen and when I was fitting the body post discover that for the rear I have 3 different options. I went for the rear one. but what are the difference between rear and mid position.

best regards
Javier

I know what is said, but haven't yet found anyone who has tried both to give me a proper assessment.

On 12th cars we run off the mid position because the downforce them goes through the centre pivot and it wouldn't work as well as a mount from the pod. On a GT12 the chassis is solid between the alternative mounts so the rear one gives more leverage to centre pivot so more force into that part of the car. However, there is also a lever from the wing to the more forward mounts so in theory the effect should be the same.

The reality is that the wing mostly provides drag behind the centre of pressure so stabilising the car aerodynamically, and the open nature of the chassis with all that air trapped under the rear of the body provides lift. I have never been convinced that a wing provides downforce, but without that drag behind the CoP the car is less stable. Do we confuse one with the other?

[QUOTE=Martin.s;921448]

Originally Posted by mark christopher

Pointless, use one or other, if you want stiffer damping use stiffer oil.[/Q

Ummm....and if you don't have stiffer oil available? Really just wondering why people don't try things that are a little more out of the box....if no one has EVER tried how does anyone know what effects it could have either positive or negative....

O rings plus dampers equal so much damping the car hardly has enough force to overcome it and roll at all, thus reducing grip and making the rear tramp in the turns.

Not every possibility needs testing when experience and the application of simple theories can indicate what will work and what won't. It didn't need any testing to know that running friction bearings in the front axle of a GT12 (as they are run in Stock Cars) would not be as fast as running rolling element (ball) bearings as we do in GT12.

So it is that we know the combination of O rings and dampers all make the car too stiff and a stiff car will be liable to tramp in corners as it has no compliance to the effects of roll and tyre slip.

Keep up the good work one and all - GT12 is still the fun class!!

[stucartwright]

Quick update from me...
New tranny turned up, Futaba T3GRS, setting it up this arvo in prep for racing at Newbury tomorrow. Excited to see the venue, looks mint online.
Have got myself some jewelry scale to balance up the new Zen...

Thanks has to go out to Mike Manning, he supplied the new Futaba for me and some body posts I snapped and the service was fabulous.

Anyhow, after ten days away on business, buzzing to get back to racing tomorrow!! Will keep you updated of tomorrow's run. Also, may post a few pics of the jewelry scales and the new tranny later.

Happy Saturday all.
Stu

[stucartwright]

RC Car Handling Link

Have found this link really informative, am sure not all of the info is spot on and maybe not bespoke to GT12 but it has some application no doubt for newbies like me.

For all those interested, here you;

http://users.telenet.be/elvo/

Best Wishes
Stu

[stucartwright]

My weight system without car

[stucartwright]

Forgot the picture!!

[stucartwright]

My Zen after being balanced on a balanced surface before anyone ask 😎

[mark christopher]

[QUOTE=Martin.s;921448]

Originally Posted by mark christopher

Pointless, use one or other, if you want stiffer damping use stiffer oil.[/Q

Ummm....and if you don't have stiffer oil available? Really just wondering why people don't try things that are a little more out of the box....if no one has EVER tried how does anyone know what effects it could have either positive or negative....

Put simply I posted that answer as it has been tried and tested, that was the results. I would not recommend the side dampers if your not going to buy any different oils.
Feel free to try it your self.

[shinytopman]

Slowone many thanks for that. Very usefull , might well be getting the iron out if i get time.
Many thanms.

[stucartwright]

Reading various FB pages, it appears Schumacher have to step up to the plate, momentum is gaining for the likes of Zen, Ore and Mardave...

Very interesting to read the views across all the spectrum of drivers.

Fascinating to see what Schumacher come up with, do they go more simplistic out the box experience, or keep complexity. I am definitely not a leading light in all GT12 but I have had very recent experience of being a newbie....

It can only be a wonderful thing for GT12. Newbury car club tomorrow for me, can't wait.

Over and out.
Stu

[draperst]

Originally Posted by mark christopher

both my cars

Hi Mark, how did you get your esc so close to your servo? I tried it but the wires run out of the left hand side, would appreciate your insight. Also what lipo connectors are they? Thanks! Stuart

[mark christopher]

I open the servo, re-solder the wires and route then through the bottom of the case and plug the side hole.

the top pic has mbmodels balls out connectors and the bottom sore/schumacher

[draperst]

Thanks Mark

[draperst]

final question for this evening (I promise) I bought a cheap radio set for my sons car and now my car. More trackstar stuff... on trying out both cars this evening, the steering gets "stuck" on both and its quite unresponsive, I think this is a case of buy cheap, buy twice as I assume the cause of the servo delay is the radio gear as it affects both cars running a core 5008 servo. If you think this might be the case I will send them both back, and may be you could recommend an alternative (Wheel type), that will not break the bank?

Thanks all

Best
Stuart

[mark christopher]

Have you tried a power cap in the received, Google spectrum power cap to were what I mean

[SlowOne]

STM - Get the iron out...? You wear clean, pressed shirts to an RC club? Now that's impressive!

[SlowOne]

Originally Posted by draperst

Hi Mark, how did you get your esc so close to your servo? I tried it but the wires run out of the left hand side, would appreciate your insight. Also what lipo connectors are they? Thanks! Stuart

I did the same without taking a solder to the servo.

Take the baseplate off, slide the rubber grommet along the servo wire and then carefully remove a small amount of plastic from the baseplate so the wire can exit straight back from the servo. Screw the baseplate back on and then fold the wire along the bottom of the baseplate, holding it in place with some Shoe-Goo.

If you ever want to sell the servo, the grommet will go back and the wire can be restored to the original position.

Note that when you do this you will break the paper seal on the servo and your warranty will be void. HTH

[stucartwright]

Today was an amazing day.. My newbie pal, Geraint, and I headed to Newbury for a charity day at Newbury RCCC, supporting local charities and a Classic Car Show. Loads and loads of spectators, kids specific race where they could turn up and drive TC's, GT12's and even a GT10!

The galleries as you will see from my picture were three and five deep at times, nothing short of a flying success, for RC and GT12 alike. Huge congrats has to go to Kevin and his team at Newbury RCCC for putting on this day, never been to Newbury RCCC before, can definitely say we'll be going back and they certainly welcome two newbies with open arms!

The Zen was a huge success for me personally, with almost twenty drivers, A,B and C finals, I manage to scrape into the A final for the first time with this amount of drivers. A GT12 team driver was there and I manage to get within half a second of his best time which I am extremely proud of after only four months of driving.

My new transmitter, Futaba T4GRS supplied by Mike Manning at YMCRacing who incidentally gave me great service, cheaper than mainstream sites and service to match! I digress, back to it, the controller from my Core was so sharp, responsive and made the Zen sing even further with the various settings it has to offer. If you are looking for a stick upgrade from a Core I would very much recommend the Futaba T4GRS.

I'll definitely be investing in a motor fan, the D4 dan a little hot and I hear the motor fans can reduce 20-30 degrees in temp which would be useful, anyone use one of these, would be grateful of any feedback or advice!

It has never been more present the future for me is on driver improvements. With hand on heart I have a car that allows me to concentrate on this huge area, and this area only, for now 😉. Definitely feel content with all my equipment, thanks to the Zen. Of course, for me.

A couple of photos to follow...

Have a good evening all.

Best Wishes
Stu

[stucartwright]

Great atmosphere...

[stucartwright]

Boom...