Problems with my DB01R
 

Hey guys!

I have a problem with my DB01R and badly need some advice.
After now about 70 7min. runs i heard a strange chattering when speeding up quickly. A racing mate said he thinks it´s the rear belt getting loose. So i thought after 70 runs it´s not unnormal to change the belt. So i changed the rear belt, rear pulley and both Center pulleys. I built everything as per manual and still have this strange sound. It even got worse so that full throttle is almost not possible. I changed the diffs, they didn´t get loose.
Is it possible that i have to change the front belt and pulley too but it definitly sounds as if it comes from the rear end although i am not 100% sure as i can´t look at it while speeding up as there have to be the diff and center covers on to try out.
I simply don´t know what causes this chattering. It sound like a belt rolling over the pulley...
Please help! :cry:

Oh i forgot to say i tried to make the rear belt one dot tighter than in the manual but the motor gets too hot and i don´t think it is ok tighten up like that.

you will have to make it a process of elimination to be honest, take the front belt off, try it, take the rear off, try it, if that makes no difference, take both belts off, if no different, check the spur and pinion for damage, also free rev the motor (no pinion on).

If you find taking one of the belts off, stops the noise, you know it is that side of the transmission that is causing the problem, so you will need to check the bearings (diff and hub) and the pins on the driveshafts to.

Oh i hoped i wouldn´t be that answer :( it already took several hours to take it apart and built it up again twice!
I let the motor turn without pinion, nothing strange.
So maybe it´s the front belt. I will try and leave the rear one out this time and see what happens.
Will take me some more hours i´m afraid :-(

shouldn't take to long to do fella

Check all the pins in the universal shafts. The wheel axle side ones tend to slide out if the small hex screw wasn't tightened enough.

I've also had the pin in the dogbone side come loose and slide out on one drive shaft that would make a really weird noise cause it only used one side of the outdrive.

#edit.

I've got to say that is one of the biggest downsides to the DB-01 for me.
Opening it up to get to the diffs.

True, but decent hex screws and a decent driver makes life a lot better!

Concur with Pete there, first thing I did with my Durgla, converted all the screws to hex asap...

I totally agree, to have the complete gears open you need to untighten 16 M3 screws and 4 M2 screws. I did that fdor abotu 6 times now, changed the rear pulley, rear belt, Center pulleys.
Everything was fine at the last run i did until i tightened up the slipper. It may be a problem of the motor i think. If the slipper is loose it sound sweet just like the slipper sounds. When tightening the slipper and going on full throttle fast the sound comes again. It seems as if power needs to be provided quickly the motor has a problem.
Also when jumping i realized that once in the air the car gets the nose down massively which could be because the motor reduces revs too fast.
Drag brake is on #0 so that can´t have anything to do with it.
I am just more confused and don´t know what else to try.
I will go to the LHS tomorrow and let them check the motor.
Oh i forgot: If i hold the spur gear and go on 1/2 throttle quickly and the leave it the motor make this strange chattering. If i accelerate slowly even to full throttle the sound is completely normal. Strange, eh?

Is´nt it possible to modify the middle piece of the cover so you don´t have to remove it when removing the rear or front belt cover?
Have only looked in the manual, but it looks like you could remove some material from middle piece (L1).
Should save you 8 screws each time.

you can. there are lips on the front and rear belt cover, but you lose a little rigidity. Only thing I did, was cut a whopping hole in the middle cover, so I can change motor/pinion and leave the cover in place.

Maybe some debris/sand in the teeth of the spur gear or pinion?

Just an idea.

Edit to self: Read ALL posts.

If the sound comes up with tightening the slipper clutch maybe there might be some unwanted stuff between the inner slipper plate and whatever comes next?

its not somthing silly like the magnet on your motor rotor come un glued and slipping on the shaft when the car is under load.

stu

No, sorry i reassembled the slipper 3 times, everything was done correct. It seems that maybe the motor makes this sound, as from what i read it could have lost power from getting too hot 2 or 3 times. Maybe the missing power causes the chattering under stress.
Will see tomorrow when the guy from the LHS takes a closer look.
Fredrik, i also thought about cutting off some of the material to have easier access but i race on dirt and thereofore can use every seal available on the chassis although i have already thought about building and racing my NIB 511 with your covers. I think this should work too!

Can be! Is some of my latest thought!

If you remove some material (only on the top of the center cover) it will still be better sealed than the 511.:)
And the 511´s "Achilles' heel" is the rear diff and belt. It does´nt like small stones, ha ha. The belt and pulley wears out pretty fast if a stone gets in there.;)

Anyway, Tamiya could have done the DB01 belt cover a bit better. Have some ideas there.
I´m very close to buying a DB01R just to try it.

Please do it, Fredrik. I´d love to get some Fredrikness in my DB01R :thumbsup:

If your going to buy it to fiddle with, and not race, just buy a stock DB01, cheaper and easier to find...

Ha, ha Johannes. "Fredrikness"...;)

Thanks for the tip DCM.:)

Sounds like it could be your ESC/motor is the problem, check your sensor wires and wiring to your reciever
what esc and turn motor are you using?

Muratti can you make a vid (with sound offcourse) of your car when it makes that noise?
It might give us a better idea of what's wrong.

I don't think you mentioned what motor / ESC combo you are running, what gearing you are using and which battery..

If you motor massively overheated in the past, then you could have been running with a damaged motor all this time..


Also, it is not normal for a DB-01 to nose down so quickly after a jump (possibly also caused by a motor issue).. If anything, it is much easier to get the DB-01 to go tail down by staying on the throttle.

The nose should only go down if you ease off the throttle after jumping or by tapping the break.. It should especially not go down if your drag break is disabled.

I have found the DB-01 to have great aerial control while racing, so I am sure we can figure this one out..

Thanks for all your help guys. I was at the LHS and we checked the motor- it seems that the rotor is damaged. I have a LRP Vector X12 7.5 motor and an LRP SXX TC esc. The sent the rotor to LRP. We´ll see if they will change it but i think so.
In the meantime i put in a 5.5 rotor but didn´t have the chance to check if it works now because it was raining all days long. Also my NIB TRF201 arrived and i had to build it the same day i got it! Just gotta love that design. The car is very well engineered and the body looks awesome i think. :thumbsup:

Painted in PS48 Semi Gloss silver anodized aluminium. I love that colour :)

That looks nice Muratti! Do you need a backing color for that one?

apparently you need to back it up with black.

and yes I agree, that is one of the best looking single colored cars I have seen.

I would be interested in seeing some other colors like either iridescent pink gold or purple green.

fastfastout is right, it needs to be backed up with PS5 Black. I did 4 coats of PS48 and 2 coats of PS5. Thanks for the kind words.