[classicchrisk]

I have started measuring rpm on the running cars back wheel using a tachometer, which has been interesting, one car seems to have slightly exceeded the max 23k, I measured 24.5K (although it was declared as 21.5k  which is correct according to the brand tech details) on the registration sheet. My set up may not be perfect in this aspect, although I am working on improving the consistency of this testing.

That's roughly 10% over. I'd count the teeth on the pinion. If it's out by 1 tooth, that could account for the error at the back wheel. Gear is easy to check, with its colour code, but pinions aren't as obvious. After all, most of us rely on the rpm quoted on the motor wrapper, and that our power source is giving its stated voltage.

[Brumos RSR]

I agree here, stated value on the wrapper as motors could be plus or minus rpm.  I’ve purchased multiple motors from the same manufacturer and NONE of them ever hit their stated value while others were dead on in both directions and a mere one or two were outliers.  I also don’t think everyone tachs their motors prior to use, after break in and after extended use.  I found on occasion if you throw parts together without regard to anything but the wrapper, you could end up winning a few races.

[Kevan]

I don't bother 'breaking in' motors

...and if you throw parts together you're not winning ANY races

I'd say 'swollen' (aka overwidth) tyres are worth more on track than a few hundred rpm.

Incidentally, motors can improve or degrade.  I sent a Corvette Grand Sport to the last real IPS Proxy (just as Covid started), it was a 14k motor limit event with categories for rear motored, slim motored...and front motored cars which the Corvette was.
The H&R Jack Rabbit in the Corvette went tachoing at 14k and came back tachoing at 16k.

I've also seen brand new motors fail on their first night (maybe it IS a good idea to break motors in to find these duff ones before taking them to a race meeting)

[Graham]

I started measuring my own cars for another proxy, and then thought I might apply it as a test for our proxies as well. 
Basically our rules say the Max rpm as quoted by the manufacturer. So there will not be any penalties for cars with motors which out perform the manufacturers spec. 
But I will post the running RPM results I measured for the proxy cars when I have them all. And occasionally you get some entrants with motors without wrappers and a little vague about the motor grade, so could be useful to pick up any unintentional mistakes with those.
This particular car did have a motor with the Brand wrapper, so perhaps the entrant made a lucky purchase with this one 

The tyre width issue is also a case that sometimes the "intended tyre" does not end up exactly as stated, and often it is a case on measurement that one rear tyre is more swollen than the other, so one could be in spec and the other outside the spec. So you need to look at this in a pragmatic manner. But it is quite clear to me when entrants are fitting basically oversize tyres.

[BAracer]

Graham

Cars in the post!

In running one of them over the weekend, I just need to flag that you may want to dust off some of your spare penalty notices once you get your hands on my Mclaren GTR. In my defence, it's a car built for a local class that has been collecting dust and which I wanted to give a run out...do as you see fit!

The other car is a little cracker! Hopefully I won't be down the bottom of whatever scoring system you are running this time. (I put some proper tyres on my Alfa Touring Car and it runs like a steam train now!)

Good luck everyone

Regards

Fast Boy Slow

[Graham]

Graham

Cars in the post!

In running one of them over the weekend, I just need to flag that you may want to dust off some of your spare penalty notices once you get your hands on my Mclaren GTR. In my defence, it's a car built for a local class that has been collecting dust and which I wanted to give a run out...do as you see fit!

The other car is a little cracker! Hopefully I won't be down the bottom of whatever scoring system you are running this time. (I put some proper tyres on my Alfa Touring Car and it runs like a steam train now!)

Good luck everyone

Regards

Fast Boy Slow

I don’t like the sound of that, just because you’re off to enjoy yourself in the Dakar slot car Rally, does not cut it with me. If your car is outside the rules it will be forced to comply, or sent to you in France 

I decided I am not doing penalties, just too much of a headache with the scoring.

[BAracer]

Shrugs shoulders in a French sort of way... "comme ci, comme ca"

[Brumos RSR]

I don't bother 'breaking in' motors

...and if you throw parts together you're not winning ANY races

Won the 2019 Can Am Championship with my car 3 wheeling and motor taken out the package the night before shipping.

[Graham]

SPECIAL ANNOUNCEMENT
I have received a 2nd car with rear axle width outside the maximum allowed for the Event entered.
Please check before sending your cars;
Event 1 Max 64mm
Event 2 Max 68mm
Event 3 Max 65mm
Event 4 Max 64mm

At the very least the maximum rear axle width needs to be within the ranges above.

Also please check maximum rear tyre width for all events is 10mm.
I thought this would be easy with 10mm tyres across the board, but today received one with 11mm

[Graham]

SPECIAL ANNOUNCEMENT
I have received a 2nd car with rear axle width outside the maximum allowed for the Event entered.
Please check before sending your cars;
Event 1 Max 64mm
Event 2 Max 68mm
Event 3 Max 65mm
Event 4 Max 64mm

At the very least the maximum rear axle width needs to be within the ranges above.

Also please check maximum rear tyre width for all events is 10mm.
I thought this would be easy with 10mm tyres across the board, but today received one with 11mm

Just added a comment about rear tyre widths