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Great setup! I’m curious how you fare against modern cars like the B6 i.e. mid motor cars?

Absolutely slow!!

Mid-corner speed is totally different especially if corner radius is larger.
This car does not turn well if there is no braking motion.

R16 wrote: ↑Sat Dec 09, 2017 8:30 am Absolutely slow!!

Mid-corner speed is totally different especially if corner radius is larger.
This car does not turn well if there is no breaking motion.

That's disappointing. I would have expected better performance considering the front weight bias, suspension mods, etc. Well, I reckon it's time to move that motor to the front of the rear wheels??

R16 wrote: ↑Fri Dec 08, 2017 7:14 am >RC104ever

I use front B4 caster blocks and B4 rear hub carriers to lower the ride height.
For the current setting of RC10, I try to maximize initial in corners. With the wide rear tread, I could have a good exit speed with less rear roll.
Once I design (or set) the car to fit a layout and surface, I make small adjustments during practices.
(I will test different front settings next time.)

Thanks for that. I've got B4 front caster blocks but in the rear I think I'm using RPM or something, can't recall now. Interesting setup with the braces (and now that I know why), I'm going to look at mine and see if there are issues.

XLR8 wrote: ↑Sat Dec 09, 2017 10:05 am
That's disappointing. I would have expected better performance considering the front weight bias, suspension mods, etc. Well, I reckon it's time to move that motor to the front of the rear wheels??

Already!


Well, the wheelbase and front tread of my RC10 are short. I would expect less angular momentum for yawing in a mid corner.
Mid-coner speed is low because of understeer. One possibility is that it is caused by loss of front grip due to acceleration.
I have tested some adjustments (no luck so far). But I still have a list of things to do.

I'm not stating anything new here but, all other things being equal and provided there is enough rear grip to prevent over-steer, a mid motor configuration will nearly always be quicker through the turns than a rear motor; if for no other reason than it places more of the car's mass toward the center so the car rotates more easily. Tracks have evolved over the years to the point where there is sufficient rear grip to permit a higher front/rear weight bias. In formally sanctioned racing series, does anyone still compete successfully with a rear motor car?

I had thought there were guys here who raced rear motor goldpans against modern cars on the track and did really well. No idea if they raced against mid motor cars though.

Finally, I got good mid-corner speed.

I wanted to have a small amount of roll in mid corner so that I can have a front bite to overcome the under-steer tendency during acceleration. I have tried different front settings (spring rates, shock angles and shock pistons). But those changes brought too much front grip. The car had an over-steer tendency and lost agility. I put back my front setting to the my original (blue and #3 piston). Then I moved the weight on the nose plate to up and outside to make a roll from the weight shift and position of center of gravity.

I asked my friends to run my RC10 (red one) and B1.5 and took a video. He kindly upload this video on his youtube account.
https://www.youtube.com/watch?v=etZ8BEizsEo

I would like to note a few things.
・It was their first time to run my cars.
・This video was taken before above modification on RC10. Cornering speed is faster now. RC10 was slow especially in the near-side left corner.
・The track layout is vintage friendly (no big jump).

Since B1.5 was introduced above, I decide to describe my B1.5 here by comparing with my RC10.

<Introduction>

This B1.5 is T2 buggy. I use the T2 nose plate with the stock T2 chassis length and change the T2 arm to the RPM Worlds arm (dyed black). I would like to call this car B1.5(WOIN).

T2 chassis use the short wheelbase (SWB) holes on the rear arm mounts. Therefore, the distance between the rear axle and motor is longer than my RC10 (using LWB holes), and the chassis weight is heavier.
Because of this weight distribution, it is expected that B1.5 has more traction than my RC10 (and stability due to the longer wheelbase). However, in corners, it would have understeer during acceleration.

The chassis does not accept the transverse battery position and weight would be spread in the longitudinal (inline) direction. To make B1.5(WOIN) faster, I tried to optimize weight distribution and adjust suspension settings.

<Front>
・RPM Worlds front arm
・Front bumper from RPM
・Front shock tower from FibreLyte, "RC10 tower-Raymond Power"
https://www.rc10talk.com/viewtopic.php?f=38&t=33388&sid=6da407611632cce403fb197ffc9ad35f#p379717
・This shock tower allows you to adjust the roll center (I use the highest hole for a clay track)
・B4 big bore front shock
・#35 oil and green spring, outside hole on the arm and inside on the tower
・Shock tower, nose tube and suspension mounts are tightened with hex nuts
・J-concepts RC10worlds steering bellcrank (use AE nylon nuts)
・Custom Works 5deg caster block (-5deg) with B3 king pin (using outer holes)
・Stock inline steering block with GT axle (front width is close to 250mm)
・Stock ballstud with two shims below it on the steering block (no bump in/out)
・The steering servo is moved toward center with spacers

<Middle>
・B44 battery post with T2 battery holder (chopped off for shorty)
・RC10 battery cup attached by double sided tape
・ESC is moved forward as much as possible
・Radio receiver is placed on the opposite side of the ESC with 15g weight below it

<Rear>
・RPM Worlds rear arm
・Modified stock T2 shock tower with wing mount holes added
・B4 big bore rear shock (T4 rear shock cylinder is used to have enough droop)
・#30 oil and gray spring, inside hole on the arm (for tire clearance) and the most inside hole on the tower
・RC10 re-re arm mounts
・Add a 2mm spacer between the shock rod end and rear arm
・Custom Works hub carrier with 2mm spacer below the ballstud (adjust roll center to erase the leftover roll at/after corner exist)
・Axle spacer crush tubes (AS7377) in the hub carrier
・B4 top shaft with V2 slipper, and RPM B4 gear cover
・B44 rear CVA
・Custom Works rear axle spacer 0.125inch and B4 rear axle wheel spacer

<Other things>
・10.5t blushless motor
・I can run with modern cars without any problem
・In the video, black spring on front and white for rear were used (you can see that the car rolls excessively).
・Rear shock tower requires a modification to lower the shock mount positions (I will post how to do it later)
・Viper body with Velcro tape (rear is chopped off)

Please let me know if you have any questions.

<Rear shock tower> Left is the modified shock tower and right is T2 stock shock tower.

Modification is easy.
1. Put two shock towers together by using the bottom and second holes of the body mount holes.
2. Cut the bottom of the shock tower and add four shock tower mount holes by using the shock tower in the front side as a reference.
3. Add wing mount holes. Here, the second body mount hole is used for the bottom hole of B6 wing mount.

A vintage RC guy told me how to do it.

B1.5 and my friend's World's car. TC3 sticker is my respect to the originator.
https://www.rc10talk.com/viewtopic.php?f=35&t=10842&sid=ea094c5ecb58e98d965dc88880fd539a&start=210

Note that above suspension setting is for a clay track and a carpet setting is different.

Next cars are mid motor RC10s. One is the car with the flipped stealth transmission (stand-up style) and the other is the electric conversion of Nitro DS (laydown transmission).

I describe the stand-up mid first (RC10B1M-D??). I would just call RC10Mid.

<Introduction>

This RC10Mid follows the conversion method explained in below topic.
https://www.rc10talk.com/viewtopic.php?f=38&t=37625
I also added some modern twists.

This car turns like a mid-motor car but still has a good rear grip. I still feel as if I drove a rear motor RC10. However, the car is not as strong as RC10 so I run with 17.5t motor.

<Front>
・Add 20g weight around the steering servo (depending on ESC weight)
・The steering servo is moved toward center with spacers
・Front bumper from Shapeways (rapid_rc)
・Long front shock tower from Carbon works (3mm)
・B4 big bore front shock
・#35 shock oil and green spring, outside hole on the arm and center hole on the tower (different setting from that shown in the picture)
・Shock tower and suspension mounts are tightened with hex nuts
・Stock RC10worlds steering bellcrank (add one aluminum washer between the bellcrank and chassis)
・B4 30deg caster block, swap left to right to lengthen the wheelbase (shims in bottom) and to make the caster angle 25deg. ・Inline steering block with T4 axle, a part of the steering arm is cut off to increase maximum steering angle
・The ball bearing and spacer setting in the picture is used to achieve 250mm front width with B4 wheel. This tends to make the car dull and the outer ball bearing is sometimes busted if you tighten the wheel nuts too much. I don’t like this setting and I don't usually use it (depending on a track layout).
・B4 low profile ballstud without shim on the steering block (no bump in/out even with this setting)
・Above front shock setting might be too soft. I am thinking to try #32.5 with white spring with inner hole on the tower next time

<Middle> ・ESC and radio receiver behind the steering servo
・RC10 Transverse Shortie Pack Battery Cups from shapeways (Conklin Performance Designs), attached with second and fifth holes
・65g weight between the battery and motor
・I recommend to add linkages between the transmission and holes on the chassis (there are two screw holes right by the 65g weight) if you want to run with a modified motor.

<Rear> ・Losi VLA XXX-CR arm as used by Janus in this topic, https://www.rc10talk.com/viewtopic.php?f=38&t=10403&sid=aed6cedc26f8ddf0f004fe3da51fd313
・Spacers are added in front of the rear hub carrier to maximize the wheelbase
・Custom Works hub carrier with 1mm spacer below the ballstud
・Axle spacer crush tube (AS7377) in the hub carrier
・Short length shock tower with wing mount screw holes from Carbon works (3mm) for big bore shocks and B5 wing mount
・B4 big bore rear shock
・#30 oil and white spring, inside hole on the arm (for tire clearance) and the second hoke from outside on the tower
・Outer side of the shock rod end is partly scraped for tire clearance ・RC10 re-re arm mounts with long wheelbase holes tighten with hex nuts (rear side)
・Add a 4mm spacer between the shock rod end and rear arm
・B4 top shaft with V2 slipper
・B4 gear cover where only one screw hole can be used. To fix the gear cover, two screws are stuck out from the motor plate as shown in pictures and the gear cover is cut slightly to fit those screws. I also use a duct tape to seal the cover.
・B4 rear CVA (6 axle shims inside of the hub carrier for the motor side and 5 for the spur gear side, and 3 axle shims outside of the hub carrier)
・I use B4 pin rear wheels. The rear wheel is locked and one of ball bearings in the hub carrier could be broken if I tighten the wheel nut too much. I will use a clamping wheel hex in future to avoid this problem

<Other things>
・RC10 Graphite Team car chassis is used
・5g weight on the nose in the picture was removed
・How to flip the stealth transmission will be shown in my next post
The second car from left is RC10Mid

This thread is extremely helpful. Your cars are built with some excellent combinations and tuning, thanks for sharing! I love that each car has a unique setup.

Overall, which car would you say you like driving the best?

definitely would like to see some more of the DS Nitro conversion.

jwscab wrote: ↑Mon Jan 08, 2018 10:41 am This thread is extremely helpful. Your cars are built with some excellent combinations and tuning, thanks for sharing! I love that each car has a unique setup.

Overall, which car would you say you like driving the best?

definitely would like to see some more of the DS Nitro conversion.

Thank you for your compliment and question. I am very happy to share my experiences because I have also learned so many things about RC10 through RC10talk.com.

My favorite car is RC10 (first car), not from performance-wise. I just love its vintage feeling. Last week I went to a carpet track and tested the laydown RC10 for a whole day. I am very happy with results. But, after the day, I start regretting the fact that I have not run my RC10 there.

Yes, I will show how to build a laydown mid-motor car from vintage RC10 after finishing RC10Mid post.