Vintage losi xx brushless setup tips

[daz75]

Took my lads to race at chadderton yesterday and rather than sit around I decided to race my XX

Unfortunately on first practice my first set of old nimh cells lasted 3 laps

So after chatting with a couple of lads there they said I should be OK to use my lads lipos with my brushed setup

So gave it a try and it worked well for 2 races, in fact I was about half way up the field on my second run, not bad for a car that's still got 20 year old shock oil in it

Unfortunately the 3rd race brought and end to the motor I suspect the extra power of the lipo and the fact the motor hasn't been touched for 20 years killed it, after missing the final round I fitted another old motor I had with me to finish 2nd in my final, my car was getting some funny looks by people lol

Anyway after all that I'm wondering what a safe brushless setup would be so it doesn't destroy my gearbox
I already have a 8.5t trackstar motor would that be OK? Would I have to look at using a different pinion or just use the same one I was running at the weekend?

Cheers

Daz

[fidspeed]

I m planning 10.5 with a tad of boost so start with in my xx my worry is not gearbox as I remember running silly winds in the old brushed days but wishbones specifically fronts .I haven't seen any for sale for a while (I have xxx to and suffering same issue)

my boy just launched his fabiix cougar MM up the road yesterday as a trial with a decent 13.5 and a fair helping of boost and it went like a scalded cat !!

if its indoors and for "gentlemanly " races 10.5 should be safe and ample

dave

[dodgydiy]

a 10.5 would probably be ample, play with the timing and gearing to get the speed, and wont have enough torque to cause problems with the diff. my fab2000 with a 13 double on lipo as very close on performance to a 10.5

[KRob]

I use a 8.5's in both my RC10 Stealth and the B2.
Got a Losi JRX with the retro-fit XX box on it with a 10.5 and I've given it some with that - handles it no problem. I don't think you'd have any problem with an 8.5 in a XX. That's with Lipo too.
I have run brushed but whilst it feels great and it's good to be period, with the lack of decent cells forcing me to run Lipo instead of Nimh it does take more out of the motor.
I will run brushed in my more 'show' stuff that I will drive for fun but when 'racing' vintage it'll definitely be brushless.
Heard stories that a Hydradrive wouldn't be up to modern power though so wouldn't have one of those on (just in case you have one).

[daz75]

Got quite a lot of spares so wishbones should be OK got rpm ones on the front which is a bit more problematic as they would be about £50 to replace lol

How do I tell is its using a hydra drive?

[colin b]

Great to see you again Daz (only been about 20 years !!) the track star stuff is pretty good budget stuff but you will need a brushless compatible speedo (((that old mtronics thing won't run brushless))) hobbyking is the best place for budget stuff !!! Or the for sale section on here!!

[Chalkie]

I've ran my XX with a 7.5 and Lipo indoors with no problems, had a hydradrive fitted too which seemed to stand up ok. A xx is pretty light by modern standards so a 8.5 would probably be better. If i remember right the idler gear used to be the weak link in the gearbox.

[daz75]

Good to see you too col my lads where using trackstar stuff seems pretty good stuff

Worried about wrecking the thing would be gutted if I did

Maybe I should put together my dad's old one and wreck that instead lol

[fidspeed]

hydradrive is big black disc assembly in front of spur gear . if you cant see it easily you aint got one your on std slipper

regards dave

[daz75]

Thanks dave I seem to remember not liking it so I doubt I have one will check tho I usually have the slipper locked down tight so can't see me wanting one

[Retro RC]

Originally Posted by daz75

Thanks dave I seem to remember not liking it so I doubt I have one will check tho I usually have the slipper locked down tight so can't see me wanting one

Definately don't use it on a high grip Surface but if you do try about 25000 WT oil in it, as they were designed for low traction use with light oils. Think of it as a oil filled gear diff attached to you slipper

[daz75]

Cheers any ideas on shock oil for inside or outside and what should I do to the diff as it's not been touched for 20 years?

[DerbyDan]

The XX gearbox is essentially the same as what was used for the XXX series of buggies - & even in mid-motor Atomic Carbon CR2 guise these were quite happy to handle the brushless motors we were throwing at them - albeit with the more regular maintenance associated with running a ball-diff over a geared diff.

For the record I have been running a 6.5BL (an early 'mild' Hacker motor controlled with a blinky-spec LRP Sphere ESC) in my XX KW without any issues.

Its certainly worth re-building your diff/gearbox - give a good clean - re-hone the diff plates using wet & dry paper on a flat board & re-build using black grease in the thrust (AE or equivalent) & white silicone grease on the diff balls themselves. Likewise with the shocks - you can't go too far wrong with the kit set-up - red kit pistons & fresh new 30wt oil front & rear - green springs on the front & reds or pinks on the rear.... that said, I'm not actually sure what's in the shocks on my car - like you I first tried the car with the 20-odd year oil in the shocks & it went OK... to this day I still haven't re-built the shocks & the car was good enough to qualify for the Race of Champions at the first Revival & won the A-Final in its class/age category this year!

[daz75]

Thanks Dan the car was great to be fair even with the old oil came down a bit heavy on the front over the jumps but nothing too bad. Everyone was using virtually slick tyres which I'd left at home and I reckon with a bit more front end grip and my motor not going pop I would have been around the mid field, which isn't bad seeing I haven't raced for 20 years

I haven't stopped thinking about racing since Sunday think I've got the bug back the wife won't be happy

[daz75]

I've got 3 or 4 gearboxes I think so I'll try doing maintenance on one of those first my skills are poor see my thread about my lads 22 diff in the losi forum as proof