another burn out :(
 

Ran my Cat SX2 first time tonight at the club. 1st race fine - steering needed tuning as expected.

2nd race it all went wrong. All of a sudden a grinding noise and car stopped.

The U3345/6/7 Gear CNC Idler in step 5 (of the manual) is melted to bits. Having read the previous post's about the burning of the slipper I was expecting that to go - but for some reason it was the other side to the slipper.

http://i832.photobucket.com/albums/z...m/IMAG0078.jpg

Any ideas why this side melted? Did I have the nut to tight or to slack on the spring side? I dont believe I had it to slack as I had about 4-5mm of the thread showing.

Any ideas - as yes I can easily replace it, but what do I change to stop it from happening again?

Thanks

hi ran my sx2 at the weekend and i had the same probam but i cannot understan why either?

oh dear... not what I exactly wanted to hear :cry:

Going to ring MK-Racing tomorrow (where I buy a lot of my gear), see if they have had similair reports or if they know of the issue.

The part is £5.99 to replace... I hope I dont have to buy one of these eveyr week :mad:

Please keep me up to date if your racing this weekend and how it goes :thumbsup:

You're slipper adjust screw is way too tight, your slipper isn't working so something else has to give. Back it off until you see three screw theads and take it from there. I have mine about 1.5 mm from the end of the screw, that gives me about 6 feet of slipper action before it catches.

strangely my SX had iffy gears here, but I put it down to possible a tiny stone getting in there since I had to clean the teeth to get it smooth.

I bought replacements for both before I ran the car just to be on the safe side... my gears weren't stripped, just looked worn.

if its not a new car,check the bearings behind the cogs make sure theirs no slop.

its a brand new car.. 2 weeks old, was its first run out last night.

Looking at that pic I would agree with moth898 and say slipper is too tight mate

ordered a new part this morning. Guess i'll have to go with the 2-3mm thread showing for next time.

I guess thats one thing that the build instructions are never clear on - exactly how tight to screw things. They need to give torque values :thumbsup:

dont go of how much thread is showing, set it for the track surface you run on, it should slip no more than 1-2 seconds from a standing start,not every time you hit the gass,

I am sure i'm about to get shot done but i don't believe it is your slipper.
Not the first time i have seen this with the new sx2 cars, had a chat with a driver in the know, was advised that there are some issues with a batch of the idler gears give schumacher a call and get yourself a fresh one. I put in a worn gear from an sx1 that was used for all of last year, did not change the slipper or anything else and have not had a problem since. Also send it back so they can have a look.

thanks for that idea ! I'll give them a call on Monday and see what they can sort out for me.

Pro4nut is right. The latest moulding batch has poor quality plastic, schumacher are aware and will replace the gears for you with improved ones.

The schumacher instuction book, page 37, reads the the shipper should allow you to exit a turn without spinning....that, to me, means it should engage exiting turns....unless I'm misunderstanding it. I have my slipper set that way and my car runs planted. Not that I dought your experience big red, but if our friend here is a beginner like me, he should run it loose to help with a twitchy trigger finger. My setup got me third today.

it reads,
consistent drive away from the turns without spinning the car,which means set it to the track as i said, not 4-5mm thats just a recomended starting point,

rang Schumacher up directly this morning. Explained the problem.
They took the batch number from the sticker on the box - accepted that there had been some bad batches - took my name and address; posting a replacement out free of charge to me.


Can't argue with their customer support there :thumbsup:

Are they the same idler as in the Cougar? Over the last few weeks the pit area floor has become littered with munched sv idlers and bearings:woot:

Ask them?

you could check the part number with the Cougar instructions .. SX2 numbers are U3345/6/7 (depending on ratio/tooth)

I wouldnt dare...too much growlin going on!!