XRAY - Model racing cars

It is currently Fri Feb 22, 2019 10:50:44

All times are UTC + 2 hours




Post new topic Reply to topic  [ 35 posts ]  Go to page 1, 2  Next
Author Message
 Post subject: race aftermath and help needed
PostPosted: Mon Mar 24, 2008 01:52:06 
Offline
User avatar

Joined: Sat Dec 22, 2007 13:28:49
Posts: 94
Location: Kuwait
hi guys,
it's Ali from Kuwait again :)
well i raced my car for the first time last weekend and i had a blast, basic set-up and freaking fast with the TZ-5P/ nova pipe and team Titan's cooling head.

my questions and remarks are:
1- do you guys ever run softer rear tires? i always see you guys run softer front (saw this in your setting sheets).

2- everything went ok during the race (car was fast, nice response and good clutch engagment) BUT when i took my car apart today to clean it, i saw that my cltuch is not sitting right, so i took it apart too AND GUESS WHAT, i found only one FLYWEIGHT instead of 3 !!!!!, outer ball-bearing (small) damaged, thrustbearing assembly damaged !!!!!!
any ideas on what went wrong and HOW IT RAN WITH ALL THIS DAMAGE ??

thanks alot

Ali


Top
 Profile  
 
 Post subject:
PostPosted: Mon Mar 24, 2008 02:00:23 
Offline
User avatar

Joined: Sun Jan 30, 2005 01:19:02
Posts: 338
Location: Portland, OR USA
I usually try to get the car to rotate more due to the high rear weight bias, so I use softer (numarically softer). But if you take a nitro touring front tire (26-27mm) and feel them they are actually quite a bit harder than rears of the same number. a tire thats 2-5 degrees softer in front is common. On this car I have yet to run a softer tire rear. If the car is too loose look for ways to tune it out in suspension.

The 5 X 8 bearings in the clutch die fast, its a fact of life. The rest should last a while. Make sure your flywheel nut is tight, the 3mm allen size through bolt is tight.. usually when you throw flyweights on a centax clutch its because something came loose, but mostly when you set the clutch gap to large. ie over 0.7mm gap. Also with the thrust bearing, make sure the small hole is against the keeper flange(stationary part). how it ran? because this car is a tank lol.. not weight wise, I just have abused this car to no end, and it keeps going.. Nothin like your deal.. but its a good car

cheers,

Patrick


Top
 Profile  
 
 Post subject:
PostPosted: Mon Mar 24, 2008 02:26:07 
Offline
User avatar

Joined: Sat Dec 22, 2007 13:28:49
Posts: 94
Location: Kuwait
hi patrick and thanks for the fast reply

i was running 37 rears and 40 fronts, my car was understeering alot, i guess i had way more rear traction, next race i'll try 37s all around or 40s all around/ harder rear springs (red) and increase front toe to 2 degrees. what do you think??

ok i didnt understand clearely what you said about the thrustbearing instalation, do you mean the small holes toward the 3mm allen bolt?? i guess yes since this is the stationary part!! right?

thanks

Ali


Top
 Profile  
 
 Post subject:
PostPosted: Mon Mar 24, 2008 02:39:02 
Offline
User avatar

Joined: Sun Jan 30, 2005 01:19:02
Posts: 338
Location: Portland, OR USA
the front / rear compounds depend on the brand. With jaco I start with 38 front 40 rear unless the track has no grip or lots of grip.. I tried stiffening up the car, with mixed results.. give me an idea of the track and I can give you a better idea of where to go with spring.. somewhere in the short dark blue spring front and stock rear spring is a starting place unless the track is high bite. then pinks all around..

with the thrust bearing, there is one small Inner diameter hole, and one large.. make sure the small hole is closest to the flange on the holder..

Cheers,

Patrick


Top
 Profile  
 
 Post subject:
PostPosted: Mon Mar 24, 2008 02:51:49 
Offline
User avatar

Joined: Sat Dec 22, 2007 13:28:49
Posts: 94
Location: Kuwait
ok now i get it for the thrustbearing,

i use GRP tires, our track is a high traction one with 2 straight lines and wide corners, one tight U turn. over all, it's a nice big simple track, not very technical and not bumpy at all.

P.S. i live in Kuwait where we don't have Xray parts in our LHS, i order all my parts from HongKong, so i don't have anyother springs, i have the stock ones and the hard (red ones) :)

cheers,

Ali


Top
 Profile  
 
 Post subject:
PostPosted: Mon Mar 24, 2008 13:40:43 
Offline
User avatar

Joined: Sat Oct 23, 2004 08:22:54
Posts: 897
Location: Holland
Go to the hardware store and get some brass rings in the size of your thrust bearing and put one in the place of the damaged ring with the balls between the 2 grooved rings.

It works very well and no problems anymore.

Because the ring with the ball was damaged you did get a bigger gap and so the flyweights did come out...


Top
 Profile  
 
 Post subject:
PostPosted: Mon Mar 24, 2008 14:10:05 
Offline
team driver
User avatar

Joined: Tue Feb 27, 2007 14:52:28
Posts: 28
Location: Netherlands
Hi there,

The reason I always used softer tires in the front is also for the tire wear.. If you use harder tires in front, the wear is much less than the rear so in about 10 min your car has a to big split between front and rear and the car handling will be much less than before.

I used the GRP tires and 37 in front and 40 in the rear, and it works great on the most tracks.. and the wear is perfect ( that is very important for a longer race).

And about the clutch bearing, The cap and the end play is very important, but you already know that, but try to service your clutch enough. I always check my clutch a couple of time on a day, and service the bearing ( cleaning and put new (and the right) oil on it). This is the way that he wil live longer.

Good luck,
Maarten van Lierop


Top
 Profile  
 
 Post subject:
PostPosted: Mon Mar 24, 2008 14:38:53 
Offline
User avatar

Joined: Sat Dec 22, 2007 13:28:49
Posts: 94
Location: Kuwait
hi guys,

Roelof, thanks alot for the info, i was wondering how they came out!!

about the brass ring, what is a brass ring?? :)

Maarten, thanks too, i always had in mind softer fronts, but almost all our local racers told me that IT'S A BIG MISTAKE to run softer fronts because the car will oversteer and drift. next race i'll try 37front/40rear.
about my clutch, everything was set up right, gap, end play. so i'll redo it again and hopefully it will work as good as last time :)

one more question, can i use serpent or kyosho clutch weights??? or do i have to use the xray ones, am askin this question because serpent/kyosho parts are available here in Kuwait.
xray parts = hongkong order + shipping :(

thanks guys


Top
 Profile  
 
 Post subject:
PostPosted: Mon Mar 24, 2008 14:53:24 
Offline
User avatar

Joined: Sat Dec 22, 2007 13:28:49
Posts: 94
Location: Kuwait
one more question, can i use CERAMIC bearings for the clutch?? or do i have to use the normal rubber sealed ones??


Top
 Profile  
 
 Post subject:
PostPosted: Mon Mar 24, 2008 15:47:21 
Offline

Joined: Fri Jan 04, 2008 00:01:55
Posts: 18
Location: Kissimmee FL
KWT-NT1 wrote:
one more question, can i use CERAMIC bearings for the clutch?? or do i have to use the normal rubber sealed ones??


I think you may want to stick with the normal rubber sealed bearings. I do not think ceramic bearings stand up well to sheer stress. (The sideway forces exerted on clutch bearings) The can shatter.

But for centrifugal forces, they are the best so far.


Top
 Profile  
 
 Post subject:
PostPosted: Mon Mar 24, 2008 18:28:37 
Offline
User avatar

Joined: Sat Oct 23, 2004 08:22:54
Posts: 897
Location: Holland
Brass ring:

Image

Use the normal 2 grooved discs, put some greese in the grooves.
In the middel is a brass ring, brass is a well used material as a bearing, it works very well, I am using it for years. These rings will cost you maybe 5 cent and will last way longer.
Currently I am waiting for ceramic rings which should give less friction as if it would be noticeable.....

Ceramic ballbearings will work to last longer but be sure you have quality stuff, cheap Asian ceramic bearings are just as crappy as cheap steel bearings......


Top
 Profile  
 
 Post subject:
PostPosted: Mon Mar 24, 2008 18:33:39 
Offline

Joined: Fri Jan 04, 2008 00:01:55
Posts: 18
Location: Kissimmee FL
Roelof wrote:
Brass ring:

Image

Use the normal 2 grooved discs, put some greese in the grooves.
In the middel is a brass ring, brass is a well used material as a bearing, it works very well, I am using it for years. These rings will cost you maybe 5 cent and will last way longer.
Currently I am waiting for ceramic rings which should give less friction as if it would be noticeable.....

Ceramic ballbearings will work to last longer but be sure you have quality stuff, cheap Asian ceramic bearings are just as crappy as cheap steel bearings......


What end play do you run to get this to spin freely?


Top
 Profile  
 
 Post subject:
PostPosted: Mon Mar 24, 2008 18:51:04 
Offline
User avatar

Joined: Sat Oct 23, 2004 08:22:54
Posts: 897
Location: Holland
Just use the normal gap setting, endplay is not that critical, only be sure it has some play


Top
 Profile  
 
 Post subject:
PostPosted: Tue Mar 25, 2008 02:10:12 
Offline
User avatar

Joined: Sat Dec 22, 2007 13:28:49
Posts: 94
Location: Kuwait
thanks alot Roelof for all the info and details, i have a new thrust bearing, i'll give it a try once again, if it fails on me again, i'll try the brass ring.

am currently running stock gears, and i would like to shorten my 2nd speed, so shall i keep my 21 pinion gear and change the spur from 54 to 53?? will that help me ?? the 2nd speed ratio will be 4.97.
Now with the 54 spur, i get to the corner after the straigh line before getting to top speed.

thanks


Top
 Profile  
 
 Post subject:
PostPosted: Tue Mar 25, 2008 08:55:30 
Offline
User avatar

Joined: Sat Oct 23, 2004 08:22:54
Posts: 897
Location: Holland
You can take a first try with a bigger spur, changing pinion can be to much.


Top
 Profile  
 
 Post subject:
PostPosted: Tue Mar 25, 2008 12:33:23 
Offline
User avatar

Joined: Sat Dec 22, 2007 13:28:49
Posts: 94
Location: Kuwait
a bigger spur or a smaller one?? !!
you mean if am running 54 now, i should go with the 53 or 55 ?? i'm confused about this thing.


Top
 Profile  
 
 Post subject:
PostPosted: Tue Mar 25, 2008 13:09:48 
Offline
User avatar

Joined: Sat Oct 23, 2004 08:22:54
Posts: 897
Location: Holland
KWT-NT1 wrote:
Now with the 54 spur, i get to the corner after the straigh line before getting to top speed.

thanks


This confused me...
You are not getting on top speed, the engine is still reving up ?
If so you do need a bigger spur or a smaller pinion

It is depending the motor you are using, a Orion CRF wants to have a very light gearing


Top
 Profile  
 
 Post subject:
PostPosted: Tue Mar 25, 2008 13:52:49 
Offline
User avatar

Joined: Sat Dec 22, 2007 13:28:49
Posts: 94
Location: Kuwait
yes the engine is still reving up when i get to the braking point, i want my second gear to be shorter. i thought i have to use a 53 spur gear, with less teeth, the gear will rotate faster = shorter 2nd gear time , am i right ??
i run an OS TZ-5P/ nova 2630 exhaust

thanks Roelof, i know i have alot of questions :) just bare with me


Top
 Profile  
 
 Post subject:
PostPosted: Tue Mar 25, 2008 14:25:12 
Offline

Joined: Fri Oct 08, 2004 09:01:33
Posts: 1702
Location: Hampton/Va Beach USA
KWT-NT1 wrote:
yes the engine is still reving up when i get to the braking point, i want my second gear to be shorter. i thought i have to use a 53 spur gear, with less teeth, the gear will rotate faster = shorter 2nd gear time , am i right ??
i run an OS TZ-5P/ nova 2630 exhaust

thanks Roelof, i know i have alot of questions :) just bare with me


For a shorter 2nd gear you go larger on the spur (54 to 55). Here is the rule:

Taller gearing = smaller spur or larger pinion

Shorter gearing = larger spur or smaller pinion


Top
 Profile  
 
 Post subject:
PostPosted: Tue Mar 25, 2008 15:00:43 
Offline
User avatar

Joined: Sat Oct 23, 2004 08:22:54
Posts: 897
Location: Holland
Yes, to get a lighter gearing to get the engine better in high revs you do need a bigger spur or a smaller pinion.


Top
 Profile  
 
Display posts from previous:  Sort by  
Post new topic Reply to topic  [ 35 posts ]  Go to page 1, 2  Next

All times are UTC + 2 hours


Who is online

Users browsing this forum: No registered users and 1 guest


You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot post attachments in this forum

Search for:
Jump to:  
Powered by phpBB © 2000, 2002, 2005, 2007 phpBB Group