gwhiz

iTrader: (1)

Someone asked. So I answered them.
You decide why it matters. Or does not.
Cheers

old_dude

iTrader: (1)

The original question is what I question.
You answered them and that is legit.

theproffesor

iTrader: (66)

Maybe I asked out of sheer curiosity? Maybe I was trolling Bert. Maybe I was generally trolling the thread and you took the bait.

My question, if you actually read it (I know reading comprehension can be hard, I am working on it now with my pre-schooler), was regarding the RIM not the tire. As these are being sold separately and not just as premounts. That can make a huge difference in performance if a significant difference exist.

A couple grams per wheel, no big deal. 5g or more per wheel could start to be something to think about. And no I’m running down the Bert road with this looking for .5g of weight savings drilling a spur gear type crap.

Years ago when we ran open tire TC at a local track the Schumacher premounts came in at nearly 40g lighter per set than the Jacos. Guess which ones everyone ran until time to get set up for snowbirds? Thats also a pretty decent amount of weight to add back to chassis for legal minimums.

So… if PF rims or HPI rims were only marginally heavier, then running those for a more scale appearance wouldn’t hurt the stellar performance of the new tire. But if they are significantly heavier, then I would only mount up a set for concourse competitions.

Thanks to those that actually answered.

Dan

iTrader: (75)

Sorry, couldn't make it to the track due to weather. The joys of Midwest winters... will test next weekend.

I can't be the only one that has ordered this motor!

gwhiz

iTrader: (1)

Hello again.
I realize that you meant just rims, not pre-mounts. So for anyone who is still interested:
I don't know where to get Protoform rims without tires glued to them. But I dug deep into my fun boxes and found some clean HPI's to weigh.
HPI (5 spoke) Front 11.9, Rear 14.5
HPI (8 spoke) Front 12.9, Rear 16.1
Gravity RC.....Front 12.3, Rear 15.2

Also while fiddling with them, I noticed:
The Gravity wheel is very stiff. Like ABS stiff.
HPI wheels (and Protoform) are Nylon. Very flexy. Chewy.

Finally, I could boil off my worn out Protoform set and clean the wheels up for weighing, but that will take a minute.

theproffesor

iTrader: (66)

Thanks for the additional info on the flex of the rim. driving in carpet or asphalt could be beneficial depending on desired performance.

Looks like weight is a non-issue.

old_dude

iTrader: (1)

I will tuck my tail on the wheel weight. I am a engineer and race cars so rotating inertia, wheel flex and sprung/unsprung weight are all in my wheel house. What I didn't know was that they were sold unmounted to give you a rim option.
But on the other hand I am sure that major races and maybe series will require the pre-mounts and maybe even do race handouts to prevent insert funny business.

STLNLST

iTrader: (32)

the spec motor would never have a chance at the home track of Team Powers ☺️

belewis01

iTrader: (5)

Random thought on the spec motor ...... one of the replies when I object to a spec motor is - " well, your race director can always call out for open motors".

Well, doesn't that work both ways? If open motor is too fast for your track, couldn't your race director require spec motors?

I have a feeling, one day soon, someone who has never asked for my input is going to dictate spec motors, and force those that don't want it to either change, drop out or convince race directors to follow the old rules.

glennhl

iTrader: (16)

It was interesting how we adopted the spec motor for USGT. A couple of guys that really wanted to get rid of the motor of the month club got the spec motor and started racing in USGT. They were giving away some speed, but not a lot. Then when the rest of us realized that this $80 motor worked and seemed very equal to each other, we all jumped on the bandwagon. Only then did our Race Director require us to run spec motors, only after 90% of us had already changed over.

old_dude

iTrader: (1)

This might happen in VTA. There was another manufacturer that offered a FT Spec motor to Rob. It was tested at our track and it was just as fast as anyone's "open" motor in October. Times have changed with the new TSR and Motiv 25.5's for open. And Rob apparently picked the Gravity motor. As far as acceptance, we will see. The USGT motor has been good.

glennhl

iTrader: (16)

A very good open 25.5 motor is just about as quick as the USGT spec motor. So if the FT Spec motor is as fast as an open 25.5, it is almost as fast as the USGT spec motor. I always thought they should have just gone to the USGT spec motor for VTA, but Rob obviously wants VTA to be slower than USGT, which I can see. So Paulie gave him a 25.5 spec motor timed at 30 degrees that fits the bill. And the nice thing about 30 degrees is the motor won't get hot and will last a long time. I still run my original USGT spec motor and it's around 3 years old and has been run a whole bunch and is fine.

old_dude

iTrader: (1)

The new 25.5 open motors are a lot quicker than what was on sale in early November.
Here are the fastest lap times from the Hudy race.
VTA - 11.6 (new Motiv)
USGT-10.9
25.5 TC - 11.1 (new TSR)
Stock TC (assuming open 21.5) - 10.4
Just food for thought.

robk

iTrader: (22)

https://www.usvintagetransam.com/rul...s1-16-2024.pdf

MonkeyCmonkeyDo

iTrader: (4)

Booo