X5 spur gear and more

[cmgreen]

Guys,

Only had my x5 a couple of weeks and gone through 2 spur gears, my own fault, not meshing properly, but at £11 quid each its getting to be expensive. Can you buy different ones?

Also, is the slipper ment to slip, cause i have heard to keep it tight so it doesnt damage the pucks on the slipper.

[super__dan]

The spur gears are custom, hand made for the car, hence the expense. The one on my car is the original one from the start of the 2007 season. I have been meshing mine properly though ;)

Slipper setting is up to you. Best is to let it slip just a fraction on take off from a standing start on a surface of reasonable grip, this will then protect the rest of the tranny.

I had to laugh slightly at your comment that someones said to have it tight to protect the pucks as the pucks are the very component designed to wear out and so are the consumable components. If you're protecting those, it's too tight and so will pass the strain onto all the other tranny items so expect to go through drive and diff pulleys and belts MUCH more often than you would otherwise. The front diff and drive pulleys in my car are also originals from the start of the year in my car, I did preventativy change the rear one when I had the rear diff out last, so have used 2 all year.

[Paul_Sinclair]

When we originally designed the X - 5, back in like 2003/2004, we wanted to use the XXX-4 spur gears, either the 92 or the 94 spur. Unfortunately, it was just impossible to get the gearing right with that small of a spur - because the internal ratio of the car is only 1.75, with a 94 tooth spur gear we ended up using like 13 or 14 tooth pinions. The larger spur gear really opens up the gearing options.

So, since we had to make spur gears, we went and found the best gear-machining company in RC: Precision Racing. They do charge us a little more, and thus the spur gears are a little pricey, but if you treat them right they'll run forever. I've used the same 3 spur gears (a 102, 104, and 106) for the last two years at least.

I suggest really taking time when you set the gear mesh. Be really careful as you tighten down the motor strap, as it can sometimes shift the motor one way or the other as you tighten. I usually tighten the bolts together - one turn on the front one, one turn on the back, one turn on the front, etc - and examine the gear mesh frequently as I tighten. Make sure your pinion gear is in good shape too - I don't usually think of pinions as wearing out, but just this last summer I took a hard look at my pinions and replaced a lot of them (they were like 6 years old, lol).

So take some extra time setting the mesh, checking often as you tighten down the screws, and the spur's should last a good long time.


If you're the adventurous sort, you might check into finding some on-road spur gears from a touring car. You might be able to find one that you could make work; I don't know. Not sure I'd recommend it as the gears are 64 pitch and thus even more fragile, but the gears themselves might be cheaper.

[cmgreen]

Cheers guys,

The gear mesh was my fault, totally. So the slipper pucks are a consumable, thats all i needed to know, i will set it so it slips on power from a standing start on a grippy surface. i.e. teeside.

I also got some machined pulleys from lesro, which seemed to be too big, its melted away and knackered the belt. Am going to go for the xx4 rear diff pulley with the xx4 17t pulley. Also just ordered the second idler pulley people seem to be taking about try and kill some belt skip.

Just a note, didnt skip at all with a brushed motor in, just when i put the brushless in.

Over all seems a fast car, as long as i can get the transmission set correctly.

[super__dan]

HIya,

Not sure I follow on the pulley thing, they only come in 1 size which is the same as the stock X Factory ones. I run the 17t xx4 centre pulley as unfortunatly the stock X factory one is not perfectly round. That and a hold down roller in front of the pulley makes a MASSIVE differene to how slack you can set the belt with zero skip.

If you come to what is likely now a club meeting at Batley on Sunday I can show you these mods on my car if you like?

Ref the slipper again, it shouldn't be slipping much, just a wafer on standing start take off. Also when you take it apart you might see that the spur can 'wobble' side to side by hand. This is correct as the slipper pucks are wider than the spur so the slipper plates clamp on them and not the spur gear. Your pucks are worn out when they have worn to the same thickness as the spur so the tension of the slipper is clamping on the spur gear and will very quickly wear that away.

There is a slipper rebuild kit avaibale for the Losi XXX4 which is excatly wht you need when it comes to maintaining it, it comes with a couple of washers and odd spring things, just chuck those away, it's only the pucks you need.

[bigred5765]

just i quick thought when u said the machined pulleys melted away and ruined your belt ,you did remove the little pips from the bottom of the bearing holders as mentioned in the manual didn't you,

[Gayo]

Am going to go for the xx4 rear diff pulley with the xx4 17t pulley.

By doing this, the internal ratio will be very tall so be sure to use a mild modified and/or a very small pinion. Check the overall ratio here : http://www.4wdrc.com/tech_X-5_drive_ratio_chart2.htm

Like Dan, I strongly suggest to use the X-Factory or Lesro diff pulley and a XX-4 17t center pulley. The hold-down roller is a must on astro but I found the second idler useless.

[Fiddybux]

Where would you guys recommend putting a roller bearing to minimise skipping. It seems more accessible to put it up on the spur side (and under breaking this would be he area where the belt would lift off).....but putting one near the pulley might be more effective.

What do you reckon?

[Gayo]

I run with both rollers. The most effective is the center one, the rear one is more for ears convenience. If you don't use it, your belt will skip slightly on heavy brakings.

[Chrislong]

Hey Russ,
I use the optional large pulley for the XXXS to lift the belt and the small kit black pulley for tension. That makes a big difference to start with.

Then when looking down on the spur with the cover off, I have a 3/8 x 3/16 bearing on a roller over the belt. It is close enough to touch without pushing, the idea is that because the belt has to lift off the idler for the teeth to slip, it is not possible with the bearing there.

You'll need some sort of alloy collet to mount the bearings on, held with washers so it doesn't wander, and then a screw through a hole in the chassis.... I have e-longated my hole so the position of the bearing can be adjusted - as it was easier to do that than get the measurements spot on first time.. and with washers, the e-longated hole can't be seen anyway.

The bearing roller made a HUGE difference to belt skip :D

Chris

[super__dan]

Mine is mounted almost directly in front of the main drive pulley a hairs width from touching the belt. I now have a VERY free transmission and no skip whatsoever..

[bigred5765]

right infront of the pulley i have pics but not of my car this is what i used to do minehttp://www.hobbytec.co.uk/index.php?ind=gallery&op=foto_show&ida=114

http://www.hobbytec.co.uk/index.php?ind=gallery&op=foto_show&ida=113

[Chrislong]

I'll show anyone trackside who wants to see.

Will be at York Saturday night, and Batley on Sunday. Worksop the follwing Sunday and Teesside Aces Sunday after that.

[bigred5765]

omg
chris u show urs and ill show mine hehehehe

[Fiddybux]

I did in my second spur gear today and this time it wasn't meshing that was the issue.

For some reason the middle of the spur gear has rounded off so it spins on the shaft and is no longer tight fit.

The slipper plates have also cut into the sides of the spur gear, although the pucks seem okay (unlike last time when they were noticeably warped and blackened in parts).

I guess what has happened this time is that the slipper was too loose and it slipped loads, to the extent that it also rounded the centre of the spur gear.

Of course, now, even with the slipper tightened right up the car won't run under significant load from the motor because the slipper shaft just spins within the spur gear (or the spur gear spins around the shaft as it is driven by the motor - but doesn't engage and drive the belts as it is rounded).

Clearly the slipper setting is absolutely crucial and if I notice any slippage during the run (today it was slipping most of the way on the straight as I accelerated) I should come off and adjust immediately.

Can anyone confirm, correct or embellish upon my experience here?

Thanks (and Happy Birthday to me!):)

[Big E]

Your right, if it slips too much it will just heat everything up and your sur gear took the brunt of it.

This also happens if you run the belt too lose and it skips then that will heat it all up

E

[Paul_Sinclair]

The spur gears come rounded in the center, just big enough to fit around the slipper shaft. When you put a new one on the shaft (gear only on the shaft) it should be able to spin around. Otherwise the slipper would never be able to work.


The center hole can warp and grow under excessive heat, which certainly would be caused by too loose a slipper.

Here are the parts that should be on the slipper shaft after the drive pulley:
slipper plate, spur gear with the six pucks in, second slipper plate, a small shim or two to adjust end float, a bearing, a wider silver spacer (around like 5 or 6 mm wide), the wide plastic spring holder, the spring, the thin plastic spring holder, and the slipper nut. If you have all that stuff on there, you should be able to completely collapse the spring by tightening down the nut. From completely collapsed, back the slipper nut off about 1.5 turns, and use that as a starting setting. I wouldn't run more than about 2, 2.5 turns off of completely collapsed. If some of those parts I listed above are missing (I'm thinking mostly of the wider silver spacer), you would not be able to collapse the spring fully because the threads on the shaft would run out first. This could easily lead to a too-loose slipper setting.

Happy Birthday!

[Fiddybux]

Okay...cool Paul...thanks.

I couldn't remember if the centre of the spur was rounded or squared off...but now you mention it I do recall it being round.

Now though, it is massive and you see where it has warped in the heat.

I don't understand why it could not run under load when fully tightened though as the spring was certainly fully compressed.

However, it could be because the slipper plates had chewed into the spur a bit and so was overall not as tight as it could be.

I've got some new spurs on order, so I'll check this all out as per your instructions when I'm rebuilding. Got no racing for 2 weeks so plenty of time to tinker.

Cheers.

[Chrislong]

Happy birthday Russ!!

Do you still have my email address to hand? if so, please can you remove the top cover from over the spur, take a photo and email it to me? If you can include the whole length of the layshaft from directly above, then I will confirm if built right - and if not, take a photo of my car and email it back to you.

I am not doubting you, but without the car in my hands its hard to diagnose a fault so starting from the basics is the easiest way.. ;)

Also, will you be racing between now and the Southport GP? As I will be there and will gladly go over anything then for you mate.

Chris

[super__dan]

Are the ucks fubar now too? Are they still wider than the width of a new spur?

[Fiddybux]

Hey Chris and Super Dan!

Cheers for the advice guys.

The pucks are ok, and not really a problem as they're dirt cheap. I bought several packs not to long ago so all good on that front. The little shims that come in the slipper rebuild kit are very handy too.

Where are you at over the next couple of Sunday's Chris? If you're not too far away maybe I'll swing over for a chat. Failing that it'll be the GP for some last minute tweaks.

I really want to get this sorted for good this time. I love the car and it loves me. We drive well together. Even with crappy baldy scummy greens (properly bald from running in the street!) on carpet it was a killer machine through the bends and had just the right amount of power slidage! ;)

Tail end of last outdoor seasons in the rains at Southport it was a bad ass momma jamma. I love racing in the wet and the X5 just makes it even better for going forward sideways!

Take it easy and have a merry Christmas.

[Chrislong]

Hey Russ,
As far as I know there is no racing on for the next two sundays.... but if you know of any please correct me, as I am in need of somewhere to go, LOL.

My next meeting is Worksop on 6th January, and then SRCC on 13th..

[minichamps11]

Hi,

Just bought a second hand X5 and stripped it down to rebuild over the weekend. I noticed that the X5 slipper pulley isn't round so dropped the XX-4 part in, however I can't get the spur gear to run true.

The slipper shaft is slightly smaller then the hole in the centre of the spur, so the spur runs out of round and moves up and down affecting gear mesh. Is this normal? The spur is a white machined one, no idea how many teeth as it doesn't seem to be marked (and there are way too many to count!).

Any tips or do I need a new spur?

Regards,

Ian


Quote:

Not sure I follow on the pulley thing, they only come in 1 size which is the same as the stock X Factory ones. I run the 17t xx4 centre pulley as unfortunatly the stock X factory one is not perfectly round. That and a hold down roller in front of the pulley makes a MASSIVE differene to how slack you can set the belt with zero skip.

[bigred5765]

cant say i have ever noticed up and down movement the spur, there is a little side play

[Chrislong]

Sounds like the spur is Fubar'd, they can wear. If there is slop in that centre hole on the layshaft id certainly recommend retiring the spur.

With the XX4 pulley (it is 1 tooth bigger than the X-factory pulleys), you will need a shim as the gear is narrower than the stock pulley - and you don't want your layshaft floating around.

[super__dan]

As above, only other thing to check is whether the layshaft is bent?

[_sleigh_]

Dan/Chris,

Having not ever seen a X-5 slipper in a state of disassemble before, is it possible to re-drill the centre of the spur to accomodate a bearing. This might help reduce the friction/wear when the spur is 'slipping' against the layshaft.

Just a thought, as it might save the cost of a new spur. I know it's not a job for a dremel, but I'm sure a friendly engineer could do it quick smart.

[super__dan]

It would as long as the bearing was no wider than the spur (narrow), has the same ID as the OD of the slipper shaft and you could drill it dead centre. None of which would be easy.

To be honest though what spurs have bearings in normally? I don't think it's necesary as I know my slipper is nearly locked, slips way less than my 2wd which doesn't have a bearing on the spur.

If this one is FUBAR then it just must have been running slipping for ages I think. Also sounds a good idea to upgrade to the 108 or 110 spurs (newer ones) which are better with brushless motors IMHO.

[bigred5765]

chris kiddys on this weekend

[Chrislong]

chris kiddys on this weekend

ok, there must be a reason you have said this here - :confused::lol:

Yeh that would work Phil, it'd be a bit excessive for a slipper though - they only wear like this if they are allowed to slip far more than they need to - i.e. screaming its tits off for 3 metres. I run my slipper tight, and spurs last ages and ages - but I have fallen fowl of melting it in the past. (Let it slip like mad at Oxon national)

[Northy]

I bet Jim could do it with his eyes closed, and one arm behind his back. It'd be to less than a thou too :p

G

[_sleigh_]

It would as long as the bearing was no wider than the spur (narrow), has the same ID as the OD of the slipper shaft and you could drill it dead centre. None of which would be easy.

To be honest though what spurs have bearings in normally? I don't think it's necesary as I know my slipper is nearly locked, slips way less than my 2wd which doesn't have a bearing on the spur.

If this one is FUBAR then it just must have been running slipping for ages I think. Also sounds a good idea to upgrade to the 108 or 110 spurs (newer ones) which are better with brushless motors IMHO.

Yeh that would work Phil, it'd be a bit excessive for a slipper though - they only wear like this if they are allowed to slip far more than they need to - i.e. screaming its tits off for 3 metres. I run my slipper tight, and spurs last ages and ages - but I have fallen fowl of melting it in the past. (Let it slip like mad at Oxon national)

Yeah that's cool... I know it was an OTT idea, but I didn't know if it was a common problem..

[bigred5765]

[QUOTE=Chrislong;100643]ok, there must be a reason you have said this here - :confused::lol:


Hey Russ,
As far as I know there is no racing on for the next two sundays.... but if you know of any please correct me, as I am in need of somewhere to go, LOL.

thats would be this lol

[bigred5765]

I bet Jim could do it with his eyes closed, and one arm behind his back. It'd be to less than a thou too :p

G

i know of a man that works to microns :yawn:a thou would be hugh to him:woot:

[_sleigh_]

ok, there must be a reason you have said this here - :confused::lol:



Hey Russ,
As far as I know there is no racing on for the next two sundays.... but if you know of any please correct me, as I am in need of somewhere to go, LOL.


Yeah but Chris posted that back in December. :p

[bigred5765]

dont usually spend the time to check dates on every post i reply on

[Chrislong]

dont usually spend the time to check dates on every post i reply on

Ha ha, it is comedy tho Carl :thumbsup::lol:

[minichamps11]

The problem is that the hole in the centre of the spur is about 1/2mm diameter bigger than the shaft.

The spur does look like it's been slipping for ages. Just now I tried to set the slipper as per the manual & had the slipper nut jump and slip down the layshaft. The thread looks knackered so no surprise there. I guess the nut's been jumping in use, killing the spur. I'll be getting a new spur, but was a little shocked at the price of a new layshaft. Having said that, it's not something you'd normally need to replace......:( I'm going to try a new nut and keep my fingers crossed.

I tend to use 10x2 / 9x2 brushed Checkpoints in my 4wd, so with that in mind, is a 108 spur the best overall choice with the XX4 pulley? What size pinion for a 10 turn?

Next question: the car is fitted with narrow alloy rear pivot blocks (from a Losi 2WD?) so that the wishbone pivot pins sit closer to the centre line of the car than my XX4. The wheel hubs are fitted to the outside pair of holes on the new style rr wishbones.

As the driveshafts only just sit in the rear diff outdrives, I'm guessing this makes the rear of the car wider than standard. Any clues what this does to the handling? Am I better off with the standard XX4 setup?

[bigred5765]

Ha ha, it is comedy tho Carl :thumbsup::lol:
:p
hmm lol

im pretty sure mine doesnt move any were near that much ill be at kiddythis weekend i have spares u can compare if ur there :thumbsup:
i have layshaft and spur gears
on a 10x2 reedy we were on a 108 x 20 or 22 outdoors depending on the track
sorry no idea on the rear track width of the car

[super__dan]

I defo used to run a much smaller pinion than that on checkpoints (10 *2's), 17 sounds familiar.

[bigred5765]

agreed dan on the check points