Schumachers new 2WD - The checklist

[glypo]

I have been thinking about this all day. I'm sure it's no secret that a 2wd is on the drawing board and I have heard its release is pending on the success of the CAT SX. That's certainly the rumour flying around the internet anyway, so nothing secret.

I have heard other rumours about it, but don't think I should really disclose them. However, I have been thinking what I would really like to see on a new 2wd, and basically have come to a conclusion.

I would like a Schumacher Cougar 3.

Firstly, and most importantly a nice shallow chassis like the original Cougar and Cougar 2 (and Top Cat). And either made of aluminium like these originals, or how about carbon made in this style? Check this out:

http://tinyurl.com/3jk366

A great looking Top Cat - I bet that chassis would be ideal for modern 2wd, i.e. the Cougar 3. I expect tooling would be be expensive though perhaps. I am sure all will agree with me though, these earlier Schumacher 2wd's were better to drive than the later stuff like the Fireblade?

Secondly, belt transmission. I still have the original belt from '93-'94 in my Cougar 2, and it is as quiet and as effcient as ever. Not that the gearbox wasn't okay on the Fireblade, I just think the belt is better. Less maintainence, more effcient and less noise.

Thirdly, front bulkhead being non-existent. One of the major weak points on all the 2wd Schumacher I have owned are the plastic bulkheads up front. If it was an alloy chassis, I would prefer a technique like the Havoc. With the Havoc they just bent the chassis at the front to provide the kick-up - then the suspension mounted direct to chassis via pivot pins / blocks.

Finally, and probably easiest to achieve as all 2wd's are, LiPo ready.

Over to you, if Schumacher decide to release their 2wd - what would you like to see?

[jeroen206]

Nice Topcat BTW

That would be great , to have a Cougar 3
A updated Cougar 2 with with UJ's and a carbon tub.
With a moulded transmissionhousing and narrower belt (less drag)

A new version off my Cougar 2 Works Carbon


http://www.tamiyaclub.com/picturefra...6090816_10.jpg

[glypo]

Those carbon tub chassis are amazing. Very nice Cougar 2!

[matt]

Originally Posted by glypo

Those carbon tub chassis are amazing. Very nice Cougar 2!

I've got a cougar 2000 with a carbon tub chassis sitting round my parents. I would like mid motor made for LiPo.

[Welshy40]

Originally Posted by matt

I've got a cougar 2000 with a carbon tub chassis sitting round my parents. I would like mid motor made for LiPo.

Hehe well I drove a mid motor version not long after the Basildon Worlds and wasnt any good, but then again it was made by Fabiix so maybe that says it all. It had a few good ideas at the time but it was missing the real testing and devlopment which it needed big time.

Id like to see a good 2wd come from Schumacher, its been a long long time since their last good one.

[rowanp25]

im having a mess about with my old cat 3k n turned it into a 2wd. so far ive increased the front kickup, moved the motor more rearward sat th rear shocks on the front of the wishbone so reversed the rear end basically also currently trying a 5/ 1 config on the cells to move weight rearward as much as possible. n yeah as mentioned in ealier posts theres very little throw of weight under acceleration and braking

[matt]

Originally Posted by Welshy40

Hehe well I drove a mid motor version not long after the Basildon Worlds and wasnt any good, but then again it was made by Fabiix so maybe that says it all. It had a few good ideas at the time but it was missing the real testing and devlopment which it needed big time.

Id like to see a good 2wd come from Schumacher, its been a long long time since their last good one.

I've got one of them aswell, the FAB2000.

[minichamps11]

Firstly, and most importantly a nice shallow chassis like the original Cougar and Cougar 2 (and Top Cat).

Secondly, belt transmission. Not that the gearbox wasn't okay on the Fireblade, I just think the belt is better. Less maintainence, more effcient and less noise.

Thirdly, front bulkhead being non-existent. One of the major weak points on all the 2wd Schumacher I have owned are the plastic bulkheads up front.


Jason,

Can't think of anything worse than a shallow alloy chassis.
The Cougar 1/2 chassis used to bend easily, especially after landing from big jumps. I can live without having to worry about whether my chassis is tweaked. If you must use alloy, the RC10 showed the way to go with it's combination of deeper sides & high quality material. Apart from tweaking, alloy looks old fashioned, gets marked easily, and compared to moulded plastic, allows less integration of features like battery retention, aerial posts etc. However I can't believe Schumacher would ever create a moulded chassis due to the tooling cost.

Belt drive = bad move. One of the reasons Schumacher went away from belt drive in 2WD is because of the increased drivetrain drag on the rear wheels. This gives a "handbrake" effect, lowering cornering speeds & making the car harder to control on variable grip surfaces & inconsistent to drive.

Can't agree more with your last point though. Schumacher used the plastic bulkheads to allow adjustable kick-up angle but the B4/X6 etc seem to get along just fine with a fixed kick-up.

[glypo]

Regarding fixed kick-up, it's easy solved when stuff mounted to chassis. If the chassis is bent to the minimum kick-up anyone would want, so say 10 degrees for this example - you could use pivot pin mounting blocks angled to increase this from neutral.

I think a smaller belt as suggested above would do the trick nicely at reducing belt drag. I felt the rear belt made the car easier to drive, and more consistent- not the other way around.

As for the chassis, I can't comment on tweaking. I can only say my Cougar 2 chassis certainly looks like it has been through the wars - and it has. 14 years on original chassis - can't be all that bad?

I certainly prefer the handling of my Cougar and Cougar 2 compared to my Fireblade etc - and I think maybe the chassis has part to play in this. Either way, I certainly hope it's not some twin deck carbon fibre thing even if it's not a shallow pan.

This topic is kicking up good debate already

[Answer-RC-Pete]

Two thin HD Belts - thinner in total than the original Cougar belt and running a gap in the middle to keep load even across the diff.. Just a thought..
I remember feeling that the belt drive was smoother than a geared drive - maybe not quite as responsive though.

[Chris Doughty]

I would throw the belt idea in 2WD right out the window for a few reasons.

- it WILL be more mainteance than a sealed gear gearbox
- the motor will go in the oposite direction to the wheels, unless you add some gears in there too, and I believe the car is mid-motor so I think they would want the snap of the motor generate some weight on the rear
- the diff will have to be too big to stop the belt skipping and get the right ratio, with would mean a high diff with no way of lowering it.
- belt drag, as mentioned before, if you want a 'softer' drivetrain, thats what the slipper does, if that works well, you wont feel any harshness from the geared tranny

there is not THAT much wrong with a twin deck carbon chassis in 2WD if the bits that bolt onto it are good. don't worry about what has been available previously.

what I would like to see

- small diam diff gear and adjustable gearbox (but not motor) height
- adjustable dogbone sweep (front/back diff movement)
- big bore shocks (1 or 2 mm bigger than the Losi shock)
- standard fitment wheels (as standard as possible - AE style front wheel)
- strong steering geomerty, able to nicely hold the wheels at full lock, no flappy wheels and beyond straight links!
- verticle inner camber link balls, normal outer camber link balls.
- 'low' front and rear shock towers

[jeroen206]

Maybe they can use the complete SX rear end .
Mid motor beltdrive.
Only need a new front end and a nice Tubchassis.

[glypo]

Okay clearly mid-motor is no secret then.

And yes exactly, I was thinking use the CAT SX style transmission. Motor then rotates same direction as wheels, sorts the hassle of getting a mid-mount motor using belts on the centre-line. This also sorts the gear ratio issues.

I don't see how it can be said belt will be more maintenance though, when it has been done before and wasn't.

For sure a twin-deck carbon chassis isn't end of world, but I think it's just too much weight up front and too high up. If there was a nicer top deck, and not to many strange plastic bits bolting it all together like the Fireblade then I am sure something good could work. As you say though, looking at the past is perhaps not the best way to judge a carbon chassis.

[Chris Doughty]

I said I believe the car is mid-motor, I don't actually know either way, I hear the same rumors as everyone else