2LikesLosi XXX-S
06-18-2003, 06:06 PM
#6451
ongbenghui: bud! you were right! it was the top shaft! i replaced it last night at the track and after 10 practice runs, no stripped spur! 
all this despite some hits with the barriers which normally (before i changed the shaft) would have stirpped my spur. 
apparently there must have been some defect on the top shaft - misaligned probably. and i dint have to do any exessive tightening of the motor clamp. thanks a lot!
highwayman: i went thru 3 spurs already before last night so it couldnt have been the spur. apparently it was the top shaft. problem solved! thanks for the suggestions as well bro!
all this despite some hits with the barriers which normally (before i changed the shaft) would have stirpped my spur. apparently there must have been some defect on the top shaft - misaligned probably. and i dint have to do any exessive tightening of the motor clamp. thanks a lot!highwayman: i went thru 3 spurs already before last night so it couldnt have been the spur. apparently it was the top shaft. problem solved!
thanks for the suggestions as well bro!
06-18-2003, 06:10 PM
#6452
Hey guys, I race with Mimno and his problem seems to be drivetrain related, so any idea's on what may be causing it would be most helpful.
His motor's and electronics are going fine in his MR4TC and he knows how to gear properly, when on the track it just seems like he's running a stock motor when everyone else is running a mod.
The car doesn't pull to one side so it doesn't seem related to one particular side or corner of the drive train, he's tried various belt tensions, at the moment it's just slack enough to make the usual XXX-S belt slipping sound under hard braking. His diffs seemed slightly tight when I fealt them but not hugely so, not enough to slow him down so much anyway.
There isn't any excess noise from his car on the track, so gear mesh seems fine, could a badly moulded spur gear still cause problems?
He's rebuilt the car atleast once so I would of thought he would notice any obvious problem, he's an engineer so knows how to build stuff too
I hope 
I started thinking of simple things he could of missed and suggested the drive hex's could be binding on the bearings, suprisingly he hadn't checked that, is this a common thing for the Losi? I know another Losi at the club had problems with getting the hex's to fit inside wheels.
Don't worry if you can't help, it just gives me more ammunition to use to talk him into getting a Barracuda R2 
His motor's and electronics are going fine in his MR4TC and he knows how to gear properly, when on the track it just seems like he's running a stock motor when everyone else is running a mod.
The car doesn't pull to one side so it doesn't seem related to one particular side or corner of the drive train, he's tried various belt tensions, at the moment it's just slack enough to make the usual XXX-S belt slipping sound under hard braking. His diffs seemed slightly tight when I fealt them but not hugely so, not enough to slow him down so much anyway.
There isn't any excess noise from his car on the track, so gear mesh seems fine, could a badly moulded spur gear still cause problems?
He's rebuilt the car atleast once so I would of thought he would notice any obvious problem, he's an engineer so knows how to build stuff too
I hope I started thinking of simple things he could of missed and suggested the drive hex's could be binding on the bearings, suprisingly he hadn't checked that, is this a common thing for the Losi? I know another Losi at the club had problems with getting the hex's to fit inside wheels.
Don't worry if you can't help, it just gives me more ammunition to use to talk him into getting a Barracuda R2
06-18-2003, 06:46 PM
#6453
Tech Adept
has he tried putting in a different motor? if he puts in a stock and is really slow, it is the car. if he rebuilt the car once, its not the car. if its not the motor, maybe he overtightened the nuts that hold the wheels on and he is pinching the bearings, making it slow. this is the only thing i could think of.
06-18-2003, 07:03 PM
#6454
He's tried about four different motors, two speedo's, two recievers, all his cells. He doesn't normally use excessive force when tightening things like wheel nuts, could be he needs some shims though.
06-18-2003, 08:18 PM
#6455
I've just done the same swap, from a Yokomo to the Losi and I noticed some of the wheels I used happily on the Yoke will bind on the hubs of the Losi.
The Hex recesses in the wheel were too deep and when the wheelnut was tightened, the outer edge of the wheels hex would rub on the front and rear hubs. It should be easy to tell if this is happening, just pull the motor out and roll the car, listening for rubbing or look on the hubs for wear marks.
If you look at the factory Losi wheels, the hex is molded quite shallow so this won't happen.
Other than that, I'd go over all the bearings and make sure they're sweet.
The Hex recesses in the wheel were too deep and when the wheelnut was tightened, the outer edge of the wheels hex would rub on the front and rear hubs. It should be easy to tell if this is happening, just pull the motor out and roll the car, listening for rubbing or look on the hubs for wear marks.
If you look at the factory Losi wheels, the hex is molded quite shallow so this won't happen.
Other than that, I'd go over all the bearings and make sure they're sweet.
06-18-2003, 08:24 PM
#6456
Originally posted by Herminator
Don't worry if you can't help, it just gives me more ammunition to use to talk him into getting a Barracuda R2
Don't worry if you can't help, it just gives me more ammunition to use to talk him into getting a Barracuda R2
Bearings maybe???
06-18-2003, 08:27 PM
#6457
Originally posted by Simon K
I've just done the same swap, from a Yokomo to the Losi and I noticed some of the wheels I used happily on the Yoke will bind on the hubs of the Losi.
The Hex recesses in the wheel were too deep and when the wheelnut was tightened, the outer edge of the wheels hex would rub on the front and rear hubs. It should be easy to tell if this is happening, just pull the motor out and roll the car, listening for rubbing or look on the hubs for wear marks.
If you look at the factory Losi wheels, the hex is molded quite shallow so this won't happen.
Other than that, I'd go over all the bearings and make sure they're sweet.
I've just done the same swap, from a Yokomo to the Losi and I noticed some of the wheels I used happily on the Yoke will bind on the hubs of the Losi.
The Hex recesses in the wheel were too deep and when the wheelnut was tightened, the outer edge of the wheels hex would rub on the front and rear hubs. It should be easy to tell if this is happening, just pull the motor out and roll the car, listening for rubbing or look on the hubs for wear marks.
If you look at the factory Losi wheels, the hex is molded quite shallow so this won't happen.
Other than that, I'd go over all the bearings and make sure they're sweet.
06-18-2003, 09:22 PM
#6458
Hehehe, I know about the axle size difference, I bought a knife edge reamer that makes short work of any "issues" 
My badly explained point was that some wheels I'd used on the Yoke(Older Frewer wheels) had a much deeper hex moulding on the wheel itself than the Losi(or Yokomo)factory wheels do.
While these Frewer wheels posed no problem with my SP, the much thinner "wheel hex drive" part on the Losi meant that the wheels inner hex moulding would rub on the front and rear hubs.
Eg,
I have some aluminium Tamiya hex drives that are 5.5mm thick, the Losi ones are 3.5mm. I used to use the Tamiya items to widen the Yokomo car slightly which meant I could run some wheels that would bind on the hubs if I used the "Factory" hex drives in the kit.
I'm pretty sure the Yokomo plastic hex drives are wider than the Losi ones so anything that was going to be a problem on the Yoke is definately a problem on the Losi...
My badly explained point was that some wheels I'd used on the Yoke(Older Frewer wheels) had a much deeper hex moulding on the wheel itself than the Losi(or Yokomo)factory wheels do.
While these Frewer wheels posed no problem with my SP, the much thinner "wheel hex drive" part on the Losi meant that the wheels inner hex moulding would rub on the front and rear hubs.
Eg,
I have some aluminium Tamiya hex drives that are 5.5mm thick, the Losi ones are 3.5mm. I used to use the Tamiya items to widen the Yokomo car slightly which meant I could run some wheels that would bind on the hubs if I used the "Factory" hex drives in the kit.
I'm pretty sure the Yokomo plastic hex drives are wider than the Losi ones so anything that was going to be a problem on the Yoke is definately a problem on the Losi...
06-18-2003, 09:33 PM
#6459
Tech Champion
iTrader: (32)
Join Date: Aug 2001
Location: In a land of mini-mighty mental giants
Posts: 8,854
Trader Rating: 32 (100%+)
If the other Losi car is working fine with the same set up then it's gotta be something simple that we all may be over looking
....thats whats slowing you down. You need to get some new Losi body clips and all will be solved..... Thats all thats left that it could be
Ohhh boy its time to go home and get outa work
06-18-2003, 10:22 PM
#6462
Originally posted by GKC
For those using the TC3 wheel hexs, what is the part number of the part to use for tamiya type of wheels?
For those using the TC3 wheel hexs, what is the part number of the part to use for tamiya type of wheels?
06-18-2003, 10:22 PM
#6463
Tech Addict
iTrader: (5)
Originally posted by ROBORAT
ongbenghui: bud! you were right! it was the top shaft! i replaced it last night at the track and after 10 practice runs, no stripped spur!
ongbenghui: bud! you were right! it was the top shaft! i replaced it last night at the track and after 10 practice runs, no stripped spur!
06-18-2003, 10:23 PM
#6464
Originally posted by ongbenghui
Hi,
TC3 wheel hex is a standard 12mm hex. I believe it should work for tamiya wheels. only the Losi come with their smaller wheel hex for Losi wheels.
Hi,
TC3 wheel hex is a standard 12mm hex. I believe it should work for tamiya wheels. only the Losi come with their smaller wheel hex for Losi wheels.
06-18-2003, 10:30 PM
#6465
Hey guys, I race with Mimno and his problem seems to be drivetrain related, so any idea's on what may be causing it would be most helpful.
His motor's and electronics are going fine in his MR4TC and he knows how to gear properly, when on the track it just seems like he's running a stock motor when everyone else is running a mod.
The car doesn't pull to one side so it doesn't seem related to one particular side or corner of the drive train, he's tried various belt tensions, at the moment it's just slack enough to make the usual XXX-S belt slipping sound under hard braking. His diffs seemed slightly tight when I fealt them but not hugely so, not enough to slow him down so much anyway.
There isn't any excess noise from his car on the track, so gear mesh seems fine, could a badly moulded spur gear still cause problems?
He's rebuilt the car atleast once so I would of thought he would notice any obvious problem, he's an engineer so knows how to build stuff too I hope
check to see if the spur is rubbing up against the tensioner,i had this problem and talked to todd hodge,he found it and had me put a shim in between the two.
His motor's and electronics are going fine in his MR4TC and he knows how to gear properly, when on the track it just seems like he's running a stock motor when everyone else is running a mod.
The car doesn't pull to one side so it doesn't seem related to one particular side or corner of the drive train, he's tried various belt tensions, at the moment it's just slack enough to make the usual XXX-S belt slipping sound under hard braking. His diffs seemed slightly tight when I fealt them but not hugely so, not enough to slow him down so much anyway.
There isn't any excess noise from his car on the track, so gear mesh seems fine, could a badly moulded spur gear still cause problems?
He's rebuilt the car atleast once so I would of thought he would notice any obvious problem, he's an engineer so knows how to build stuff too I hope
check to see if the spur is rubbing up against the tensioner,i had this problem and talked to todd hodge,he found it and had me put a shim in between the two.