Wednesday, December 30, 2015

25.5 in the USA

So 25.5 motor F1 has started to take hold in some parts of the country.  There seems to be some out there that feel that this is the wrong direction for the class.  The arguments range from "F1 should be hard" to "there will be a motor/battery war".    I'm not sure what class does not benefit from good equipment, but making a class "hard", and creating barriers to entry is not the way for what is a niche class for most.  

When the idea of 25.5 motors was first mentioned to me, I was ambivalent to the idea.  21.5 was working fine, and I didn't really see what the point was.  At the same time, I figured if it got more guys involved, that is a good thing.  There had been a slow decline in general F1 participation in many parts of the US, including Southern California, where UF1 started and built the class up.  The series was pretty much over there.

The remaining guys decided to try something at the club races: 25.5 motors.  Oddly enough, the same idea was tried in Cleveland Ohio at the Gate r/c club.  Both places found pretty much the same thing, that the cars were much more docile, but produced almost the same lap times.  Even more important, a wider range of skill levels could get the most out of the car, making better racing.

Bill Jeric and his Tuning Haus Scale Series in SoCal instituted the 25.5 motor, and they have increased F1 attendance. Both the Halloween Classic race at the Gate and the US Indoor Champs ran 25.5, and the racing was much better.  There was a lot more racing and a lot less hanging on.  Even at my home track, there is now a heat of cars weekly, where there was lucky to be any F1 racing outside of special events like the Tamiya series or UF1 MIDWEST.
I don't know if this is the answer for outdoor racing.  While a little less motor should make an easier to tame car on outdoor surfaces with less bite, the tracks are bigger.  There will still be a segment that will want to take advantage and go a little faster.

Sunday, December 13, 2015

What just happened??

Xray introduced the X1 a while ago, and proceeded to issue a bunch of beatdowns at the ETS races in Europe, among other places. Until this point, there were several ideas on how to build an F1 chassis, but most involved an inline battery.

The front ends were also hit or miss depending on which car you had.  The Tamiya front end was pretty durable, and fairly adjustable if you threw the Exotek parts on it.  It still had limitations. Speedpassion had some good ideas, but it was hard to set with the shims and graphite plate..maybe a bit complicated for what it did.  Some others like CRC and VBC tried to be a little more straightforward yet functional.

So now there has been a sudden swarm of cars based on the "Xray layout" - transverse battery, graphite plate front end parts, and often, a bellcrank steering system.

Xray  X1 2016

VBC LightningFX
Bringing back the old front end, but with the
 bellcrank instead of direct steering

Roche Rapide

Still retaining the Exotek IFS front end
TOP Racing
No bellcranks. adjustable servo angle 

Serpent F110SF2

US Indoor Champs winner, 
note machined bulkhead for upper link 

So in the last six months, there seems to have been a consensus built on the success of the Xray X1.  Only Tamiya carries on with an inline chassis configuration.  Ironically, a Tamiya car has taken second place at the most recent ETS race in the Czech Republic.  It's hard to know if Tamiya will introduce a car along these lines, knowing their desire to produce scale appearing race cars.  The TRF102 was only introduced last summer, but the TRF line would be the only way that made sense for a pure race car to make its appearance.  

In my own experience, the Xray cars have easily had .2 seconds per lap on a carpet track over a typical Tamiya car right out of the box.  They did not seem to diff as badly, and overall had much more stability.  On top of everything else, the front end adjusts easily, with all the aspects you'd like to control (camber , caster . roll center, camber gain, etc.).

Perhaps this is a sign F1 is gaining traction as a class worldwide and can finally have some staying power.

Many pictures stolen from REDRC

Monday, June 29, 2015

Mysteries of the ancient Tamiyas......

Some thoughts on the F104WGP for carpet...........


#1 My buddy Kevin is always right. Case in point, the worthless F014WGP t bar car I was running in Toledo is now pretty awesome.  He suggested the old Schumacher Shake - take it all apart, put everything in a box, shake it up and put it back together.

Key points:
soft damper/stiff tbar setting- I had the t bar pretty loose, and it rode on a single o ring.  This seemed to contribute to tire hiking and other bad things.  I made it tighter, and it got better, so I added a second larger diameter o ring around the smaller one and this again helped.  I tried 30K tube grease and that was good.  80K seemed a bit stiff, didn't let the car rotate.  50K might be the sweet spot.  BTW this is also the complete opposite of what works at the Tamiya track on asphalt.

1mm droop- less than 1mm tended to make the car traction roll old school Cleveland style...right across the nose or hinge up on the outside wheels.  More than 1mm just made it a little crazy to hang on to.

Wipe fronts with motor spray, then SXT - Until I was wiping the tires with motor spray, there was not a lot I could do with the car.  I only wiped the fronts, and sprayed the rag, not the tire.

Front end with less dynamic caster - I have a very short ball stud on the back of the arm, right on top of the servo mount.  I ran 1 or 1.5 * camber, more camber = less caster.  That's good, but as the day went on and I was at 1.5* camber the car was getting hard to drive.  1* might be the way.  Less caster over all seemed to be what the car wanted.

Straighter tie rods - Lots of corner speed.  I had 2 servo savers, one with ball studs closer together, one with wider spacing.  I ran the closer one.

Sunday, April 19, 2015

Long and short...again

Attending the Toledo round of the UF1 MIDWEST series a couple months ago, I had not been to the track for some time.  Unfortunately for me, my car was pretty much junk at the race and there seemed to be little I could do about it.  Disgusted, I decided to rebuild the car completely, similar to the top 2 cars, which were F104W GP cars.  My WGP was just not really very good.

Both guys ran the short pack, one with the battery forward, one battery back.  As in the past, I have been a big advocate of the full sized battery.  I did want to try the short pack since it was so good in these other cars, and I wanted see if that was the difference.  In my mind, I have no problem changing my opinion or being wrong if it results in going faster!

I did initially place the electronics so I could use both types of packs.  I have tried both types of packs back to back many times and have gone to the big pack almost every time.  One difference is my home track replacing the carpet with the CRC carpet from this past year's IIC race in Vegas.  This significantly improved grip levels at the track.  In the past, there was a big difference in how the cars behaved at my track and races elsewhere due to the differences in the carpet.  With the new carpet, I found the short pack to be very good, and I chose to stick with it.  At the first UF1 MIDWEST race of the year in Cleveland,  I actually went to the short pack and then reverted to the full sized pack and went faster.  However, this was with the SpeedPassion SP-1 link car and not a T bar car like the WGP.   Maybe the T bar car makes a little more grip naturally?  I'm not exactly sure.   Either way, I stuck with the short battery.

I can say this certainly did work well for me, as I was able to tq and win the UF1 round at my home track, as well as the Tamiya TCS race shortly after.  I tried the big pack during practice for the TCS race, but as the car was set up, it wanted to over rotate.

The short pack certainly has it's place.  It's a setup option as much as any other adjustment on the car.  The full sized pack is definitely useful in low traction situations, and on asphalt, as I still think it plants the car better and slides the rear tires less.  That can be a big difference keeping the rears from going off, especially on a hot day.