7.5 vs 7.0 - 6.5 vs 6.0

AdrianH78 · #1 02-06-2017

Hi all

Looking to change my motor, and I've always been curious as to is there much difference in terms of feel say between a 7.5 and a 7.0 given same gearing and motor family etc.

I guess I ask because it feels like most of the club members I race with, race with a ?.5 never a ?.0, for example a 7.5 not a 7.0 or a 6.5 not a 6.0.

For the old skool racers, I am wondering if it is like the difference between a triple or a double wind. For example with brushed motors I always found doubles too punchy but triples just right with slightly more top end.

Any advice would be appreciated, thanks

Adrian

Pushead · #2 17-06-2017

Im intrested about this difference also. Have heard that .0 are more punchy but really dont know

jcb · #3 17-06-2017

I've run the Vampire AB+ v2 motors in the full number winds for quite a few years.

I wouldn't say they are different in the way that a triple felt different to a single, more that they are in between the power bands, of half above and half below.

I always found that a 6.5 was was significantly more rapid than a 7.5, so the 7.0 is a nice middle ground for the majority of tracks I have raced on.
Using the same gearing as I would run a 7.5 and around 10 to 20 degrees of timing advance the top end is comparable to that of a 6.5, but it's smoother in how it gets there.

As always track size, conditions and layout will also determine what motor to run, but I nearly always stick to 7.0 in 2wd.

Just a note that too much timing advance can cause the motor to overheat.

Welshy40 · #4 17-06-2017

I use either a 4.5 or 5.0, the 5 has a bit more than the 5.5 and is noticeable in my car so you shouldnotice its fractionally quicker if going down by .5

mes · #5 08-07-2017

The last couple of seasons, I used to run the Muchmore Fleta modified series from 5.0 to 8.5 winds, and I always preferred the x.0 versions over the x.5s. They just felt smoother, but that may have been down to the low timing values (20°) I used to run. When I tried to run the x.5s with such low timing values, they would generate more heat und perform worse than the higher wind x.0s. If I was to run modified again, I would go for the x.0s again, but as I only hit the track occassionally nowadays, 13.5 or so will generate better lap times.