X-5 in Stock Class 17.5

[Migs]

Hi everyone,

im new to these forums, and to the x-5, which is being shipped to me at the moment, ive been reading a fair bit of good info but im hoping the x- 5 masters in here can guide me towards the light.

OK first things first, there are many factors that brought me to this car, having driven a xx4 for many years, i've grown tired of having to gear the car down due to less efficiency and lack of space for cooling for the motor, all of which is solved by this car, also the internal gear ratio is already pretty tall, 1.75 vs 2.3, making it easier to gear for 17.5.

I'm aiming around 5.3 fdr, which with the 102 spur is a 34 pinion. I'd rather use a smaller spur, and i have no issues with running no slipper, so an 82 losi spur from losi xxx 2wd with slippper locked tight should work i think, obviously no pucks, no slipper pads (though maybe one depending on spacing), any other ideas? i read in the manual, that some people were mucking around with the xxxs spur as a direct drive option, that would make the internal ratio very tall, but has anyone mucked around with this? with the 90 tooth spur, i can gear is right with a 21 tooth pinion and i'd assume i'd have to run the longer xxx4 belt and maybe the smaller xx4 diff pulleys if the belt isnt long enough. The other advantage of running the xxxs spur means theres no need for the slipper spring and nut etc to be poking out the side of the car, making arranging batteries and electrics much easier.

Sorry for the long read, i've got a few ideas going around my brain, i just want to work out if im on the right track, thanks - Miguel

[SpeedyDad]

I'm not sure on the ratios but one thing I can tell you is with the 17.5, cooling is your best friend. My son and I run 17.5s in our 2wds and the more you can cool, the higher you can gear it. We have been able to gear up quite a bit by just getting the motor cooler. I'd say with the X-5, one 30mm fan in front of and behind the motor would work well. Just make a mount or Shoe-Goo them in place

[Migs]

Originally Posted by SpeedyDad

I'm not sure on the ratios but one thing I can tell you is with the 17.5, cooling is your best friend. My son and I run 17.5s in our 2wds and the more you can cool, the higher you can gear it. We have been able to gear up quite a bit by just getting the motor cooler. I'd say with the X-5, one 30mm fan in front of and behind the motor would work well. Just make a mount or Shoe-Goo them in place

Thanks, good call about the second fan, i have a heat sink with fan attached, but a fan on the other side of the motor also would help

Still hoping someone has mucked around with a non slipper setup can help me, or is there a better place to post for help with x-factory stuff, the 4wdrc forum seems very quiet, and there arent any threads on rc tech, though i suppose its holiday season, people are probably on holidays

[Darren Boyle]

is there a better place to post for help with x-factory stuff, the 4wdrc forum seems very quiet, and there arent any threads on rc tech, though i suppose its holiday season, people are probably on holidays

to add to that there is also almost nobody from over here (UK) who will run one with a 17.5, we only run mod as a rule and these would be between 4.5 and 7.5 at best...

[Migs]

Originally Posted by DMS Racing

to add to that there is also almost nobody from over here (UK) who will run one with a 17.5, we only run mod as a rule and these would be between 4.5 and 7.5 at best...

Cool thanks, but is this the best place to post for X-5 stuff or is there a more popular forum. Also in the X-5 manual it states that people were trying the xxxs spur in the car, so im hoping someone in the family knows how they went about it, maybe i need to start a new thread with a different titile?

[YoungChazz]

Without having a manual in front of me, I'm wracking my brain trying to remember where the X - 5 manual talks about a xxx-s spur. Of xxx-4 for that matter.

When prototyping back in Jan '04, we used xxx-4 spurs. To fit them on the X - 5 shaft, we made up aluminum discs for the large center hole and they worked just fine.

[Paul_Sinclair]

I don't know/haven't read of anyone running a slipper-less X - 5, so this is new territory. "Stock" or 17.5 4wd isn't very popular at least around here in the mid-west; we run much more 19 turn, 13.5, or 10.5 classes if not full-out modified.

I don't know what capabilities you have, but I think your best bet for running a 17.5 would be to make up a disc to fit in the center of some XXX4 spur gears and run those. Make it about 75% of the thickness of the gear and everything should be able to fit together easily. You'd be able to maintain the slipper pucks that way and so the spacing should work out perfect. I do agree you'd probably end up really tightening down the slipper, but it would be there if you wanted to back it off for a slippery track or something. I think the smallest XXX4 spur gear is like 88 teeth, so you'd really be able to get down that ratio: with an 88 spur and the stock driveline, about a 29 tooth pinion would give you a 5.3 ratio.

What spur you choose shouldn't affect which belt you have to run. Even going to the XX4 rear diff pulleys in place of both X - 5 pulleys (which raises the internal ratio slightly) the stock XXX-S belt should be fine.

[Migs]

Originally Posted by YoungChazz

Without having a manual in front of me, I'm wracking my brain trying to remember where the X - 5 manual talks about a xxx-s spur. Of xxx-4 for that matter.

When prototyping back in Jan '04, we used xxx-4 spurs. To fit them on the X - 5 shaft, we made up aluminum discs for the large center hole and they worked just fine.

Thanks youngchazz, i'll look into it, the reference to the xxxs spur is on page 46 of the x -5 instructions version 1.2 under the slipper adjustment section, very first paragraph

Originally Posted by Paul_Sinclair

I don't know/haven't read of anyone running a slipper-less X - 5, so this is new territory. "Stock" or 17.5 4wd isn't very popular at least around here in the mid-west; we run much more 19 turn, 13.5, or 10.5 classes if not full-out modified.

I don't know what capabilities you have, but I think your best bet for running a 17.5 would be to make up a disc to fit in the center of some XXX4 spur gears and run those. Make it about 75% of the thickness of the gear and everything should be able to fit together easily. You'd be able to maintain the slipper pucks that way and so the spacing should work out perfect. I do agree you'd probably end up really tightening down the slipper, but it would be there if you wanted to back it off for a slippery track or something. I think the smallest XXX4 spur gear is like 88 teeth, so you'd really be able to get down that ratio: with an 88 spur and the stock driveline, about a 29 tooth pinion would give you a 5.3 ratio.

What spur you choose shouldn't affect which belt you have to run. Even going to the XX4 rear diff pulleys in place of both X - 5 pulleys (which raises the internal ratio slightly) the stock XXX-S belt should be fine.

thanks also paul, the reason running the xxxs spur/pulley would affect the belt i'd run is that the pulley on the xxxs pulley has 23 teeth as opposed to the 17 or 18 tooth pulley that comes with the car, which would make the distance travelled by the belt, but ilike ur idea, assuming i can come up with a spacer inside the xxx4 spur, that will probably be the easiest solution

[Paul_Sinclair]

Oh yeah, of course, I forgot that the XXXS spur gear/drive pulleys were one molded unit. Duh, good call.


I guess I'm just not up to par on my touring car history, something I think I'm more proud of than not....

[Migs]

Originally Posted by Paul_Sinclair

Oh yeah, of course, I forgot that the XXXS spur gear/drive pulleys were one molded unit. Duh, good call.


I guess I'm just not up to par on my touring car history, something I think I'm more proud of than not....

Hahah understood, my knowledge of the xxxs only comes out of necessity of running the xxx4 and needing to be able to gear it taller and reduce weight out of the drivetrain and avoid the whole xxx4 slipper assembly.

Oh can anyone tell me if the belt tunnel on the X-5 is the same width exactly compared to the XXX4

[Migs]

By the way, i thought i'd mention that another major incentive for me to get the X-5 was this family vibe there is here, and the fact that the top people in the company Paul S etc, drive the things, and post in forums like this helping people out, so i really do appriciate the help, hopefully my conversion kit will arrive soon, i won it on ebay off a hobby shop in the USA. Here in Australia there are a few X-Factory cars getting around, i race with Dave Warner, though i run in stock obviously and he runs mod, the X-6 has a good following here, lots of club racers switching to them and some higher level drivers too, an X-6 took out our challenge cup this year in stock, it really seems to suit our tracks, as it should with the X-5 based on the fact the xx-4 is still competitive

I'll probably follow Pauls example for the lipo battey holder, but i'll just use a xxxt battery brace, they're long enough to cover 7 cells and then i'll trim it down and drill a hole up the other end of it