So I picked up a 1/16 summit vxl yesterday and had a couple questions.
First off Im new to the hobby so I not to familiar on the typical issues encountered with RC vehicles. My other car is a new slash 4x4 so I havent need to do much besides clean it. But I do want to say Im not afraid to take these guys apart so I did take a few things out of the summit such as the trans to check it out. So here are my questions (I did search for wobble but I think my symptoms are different.
1) When lightly pressing the throttle I get some motor cogging but I also get a high pitched noise for a bit till I get to a little speed.
2) At high speeds the car wobbles and basically changes direction completely. Most of what I have seen has focused on the wheels themselves but I think my issue is that the suspension is very loose. Im think its the toe links or the push rods that seem to have a lot of play where it connects to the axle carriers. Also bearings in the the axle carries appear to be a bit loose as well. Could that be my issue.
3) My other issue appears to ooccur in reverse. I seem to hear a grinding at times but only occurs in reverse or Heavy braking. I had the gears out of the trans and they appeared good. Also the ring gear and pinion looked good too.
I might also take it to my LHS where I purchased the slash in hopes that he can help me out.
Thanks in advance
The motor issue is normal at low speeds it is called cogging. For issue number 2 I would check your steering trim is aligned properly. It may also be that your tires are ballooning and causing you to lose control. For issue number 3 I would check to see if your spur and pinion have a good tight mesh. Hope this helps
Slash, Ken Block Fiesta
I'll check the trim but I think I have it setup fine, reason I think It might be something else is if I apply a side to side motion to wheels there is a lot of play on them.
Ill check the mesh, I used the piece of paper but I might have left to big a gap.
The ESC is causing the whine... it is the electronics inside.
Loose rod joints can be tightened up with steel hollow balls.
You can tighten up the knuckles with the adjustable pillow ball caps (7033x) or alloy knuckles.
I am almost certain that the grinding is the ring and pinion. Teeth do not need to be missing or even damaged to slip by each other. Check out the thread below for more information on how to correct this issue.
Whatever it is I just typed... could be wrong.
I'll answer your second question cause I'm not sure about the others.
I thinks the steering issue is caused by a couple things. 1- the servo gears could be stripped 2- tow links are stretched out where the balls sit. 3- Axle carries and the snap in inserts have come apart, broken or stretched.
My truck is pretty bad too. Kart wheeling is bad news. I did quite a few hard crash/ cartwheels and the play in the wheels was unbelievable. My rear wheels looked like I had 10 degrees of tow in. The tow links fixed that right up.
Whining noise could possibly be from an ecessivly loose slipper clutch
Ok so I basically took the hole thing apart. The front ring and pinion of the diff was pretty chewed up so I'll be getting that as well as a couple other misc items.
Regarding the tow links, I do thinks they are stretched out.
I now wanted to ask what is the best way to clean all the misc parts? Some of the parts such as the base were easy but I don't want to scrub down every screw do is there a solution I could drop them in?
What is the lube of choose as well? I know wd40 works but attracts too much dirt?
Congrats on your purchase Crewmax, If I may add my 2 cent.
the steering issue is going to be fairly simple to correct, i would think. remember, your wheels are WAY larger than any other tire on this frame set up (ie. revo and slash) not to mention heavier. also, the knobs on the tires will cause it to roll funny. take one off and roll it across the floor or counter top. all this will translate and quite possible amplify variations in steering especially if you have slop or play in the steering blocks (knuckles). most folks are going with either the traxxas 7033x, as mentioned above, or installing aftermarket parts with upgraded ball sockets. next you may look at the end links, as stock hollow balls tend to wear more than the steel and with more tolerances in precision. certainly an upgrade here wouldnt hurt. once all this is addressed and the bearings in the wheels and knuckles are validated "in good shape' there is still some play inherant in the A-arms where they mount to the chassis. aftermarket A-arms or control arm shafts (a-arm pins) can fix this if the chassis isnt worn out.
mine too makes the high pitch noise, i have heard it in most of the cars i have owned over the year. looks like you found the grinding noise. there is a thread regarding "shimming the diff" that will allow the gears to mesh tighter and reduce the damage you have found.
lastly, and I'll shut up, regarding cleaning your parts, this is just my take and most will have their own idea here. I would use a tooth brush or some small fine bristle brush to remove the majority of gunk from your parts before washing them in soap and water. I personally wouldnt use anything that would "remove grease and oil" as it MAY affect the plastic. Not to mention, you have soap in the house already (I hope)...dishwashing liquid perhaps.
Just my experience and personal take on your situation...remember, every thing has its limit...some like to find and document those limits. That gets costly...FUN as ****...but costly. I perfer to read and learn from their "research"...hehe
Ok guys, did the tear down and car works great except for on small thing. If I spin the trans (while it's out) I feel it's a bit noisy. Recently I picked up a revo vxl which I'm also tearing down and the trans on that guy is super quiet. When I had the summit one open it appeared to be it pretty good shape and the bearings looked like they spun well. I was wondering if I should have slapped on some grease but it didnt look like there was any there originally.
What do you guys think!
did you set the gear mesh as toldto in manual? i dont, i heard somewhere that the traxxas way is too tight of a mesh
The trans will generally have some noise in it. There are multiple sets of gears and each one has to have a slight amount of play. Ive found most of my traxxas transmissions to be much noisier than those of other brands.
I would think your whining noise on initial take off was likely the slipper. When you re-built it you likely tightened it up properly and its no longer a problem.
the wobbling issue is very likely due to all the worn out parts and the play they have when you combine them all. it COULD also be a worn and soft servo saver spring. Most people don't change these but over time the spring will take a sag... this can allow the wheels to wobble even more and begin to turn the truck when it gets extreme.
Just some more thoughts for you.