Bored of mid motor 2wds yet?

[BloodClod]

The "I made this" part of Oople is one of my favourite forums - some awesome projects here. I saw the different mid motor 2wd buggies and thought they were really unique and interesting. As I never really fancied how my XXX handled I decided to take it out of storage and build a mid motor buggy out of it.

... yes yes, another one...

Started by hacking up the chassis and after some measurements the backbone of the chassis was designed and cut from aluminum and G10



The rear brace was designed to be narrow so as to provide some rigidity but yet allow a saddle pack configuration...

The battery hold-downs were fabricated next and this is how the setup looked.



Actually the hole where the antennae tube holder is mounted was actually designed as a spot for an additional stand off to increase chassis rigidity but after bolting everything up as in the pic I found the chassis didn't really have too much flex (using the sophisticated "hand-twist" test)

If you excuse the unsightly wiring, here's some simple test gear I put in there. I figure if I like the performance I'll swap it out for some higher spec gear.



Here's a pic with the ugly hacked up cover (I really don't like the color but the whole car was bought used)



Comments would be most welcome.

I'd love to hear from other mid motor 2wd drivers what your experiences are with the handling of these cars and what setup changes you've made.

Cheers,

BC

[Dunc]

I'm afraid I've no experience with mid-motor 2wd buggies (building or driving); I just wanted to say how impressed I am by your workmanship - great job!

[annie_himself]

I've wanted to do that to my BK1, if I get a CR I will do it to match my mid-motor truck.

Great craftsmanship, do you have a full chassis shot with no body?

[BloodClod]

Thanks for the kind comments.

Had the opportunity to run this buggy over the weekend. First time out the car performed very poorly - it was erratic at best. I suspected that the poor performance was caused by unsuitable rear tires and a rear diff that needed a rebuild.

Swapped out the tires for some bowties and rebuilt the diff for the next run. Performance was much improved. After some spring tuning the car started to find its groove slowly... actually keeping up with some of the 1/8s going around the track. It lost out on the straights due to the stock class motor but through the turns it was doing quite well.

It drives very different from a standard 2wd through. On power it seems to understeer but off power the car brings its rear around quite well. I had to watch the throttle at lower speeds as the rear had a tendency to come loose if I pinned the throttle too hard. At higher speeds though, it seemed to be a lot more stable around the track.

I was browsing the X-6 forums and was glad to read the experiences of the X-6 drivers. Although I'm sure my car performs nowhere near the level of the X-factory buggy, the descriptions of their buggy driving characteristics seemed similar to mine.

What are the other mid motor guys experiencing?

More tuning to do to try to get more steering on power... I probably need to fashion a way to adjust roll-center in the rear.

[Welshy40]

Well thought out and made. That is the correct way to do it and now as it is a prototype you can now develop it more via testing. Well done and keep us posted with the new ideas that you put into it.

I doubt youd remember but Tekin many years ago when Eustace Moore was racing his 4wd RC10 (Mr MIP by the way) a chassis specifically for the RC10 was brought out with the gearbox swopped around and mid mounted motor, almost like yours and the X series cars. Its not a new design but still an interesting one.

Do you reckon youd be up for putting the cells in the original position rather than side by side and put in a smaller servo so you would have room then the car to do it and that should handle a lot better and then you should have less body roll. Well its an idea that you may want to try. Still good work.

[xx4-nutter]

Cracking job there mate, after driving an X-6 mid motor 2wd car ill never drive anouther " normal " 2wd buggy again, i see them as a disadvantage now

Garry

[BloodClod]

Originally Posted by Welshy40

Well thought out and made. That is the correct way to do it and now as it is a prototype you can now develop it more via testing. Well done and keep us posted with the new ideas that you put into it.

I doubt youd remember but Tekin many years ago when Eustace Moore was racing his 4wd RC10 (Mr MIP by the way) a chassis specifically for the RC10 was brought out with the gearbox swopped around and mid mounted motor, almost like yours and the X series cars. Its not a new design but still an interesting one.

Do you reckon youd be up for putting the cells in the original position rather than side by side and put in a smaller servo so you would have room then the car to do it and that should handle a lot better and then you should have less body roll. Well its an idea that you may want to try. Still good work.

Thanks for the comments.

I did think of the layout you mentioned but I went with the saddle pack configuration as I still wanted to bias the weight distribution toward the rear of the car. Using a stick pack that occupies the space of the steering servo would move the weight a little further forward (although it would center the weight down the centerline of the car a lot more).

[Richard Lowe]

Very nicely done, puts my effort to shame

Originally Posted by Welshy40

Do you reckon youd be up for putting the cells in the original position rather than side by side ... and then you should have less body roll..

Doesn't work like that

[FERRETTI]

I admire anyone with the talent and vision to attempt projects of this nature, good on you BloodClod I hope you get it dialled

Originally Posted by Welshy40

I doubt youd remember but Tekin many years ago when Eustace Moore was racing his 4wd RC10 (Mr MIP by the way) a chassis specifically for the RC10 was brought out with the gearbox swopped around and mid mounted motor, almost like yours and the X series cars. Its not a new design but still an interesting one.

Here's a link to my shelfer Tekin for reference http://www.tamiyaclub.com/showroom_m...64658&id=18028 I'm putting a runner one together to race at Jarrow (back end of the year) so I'm also interested in the handling characteristics of such mid motored 2WDs

[losixxxcr]

i was doing the same and love the aluminum back bone idea.. but could you make 2 and mill the curve of the front side to the curve of the battery and still have the weight far enought back.. and motor movement for gearing.