Nexus

iTrader: (42)

getting back to the actual topic....


How do MVP's handle magnet rezapping?

I have a MVP that I picked up that was barely used and plan to buy another armature and maybe rezap the can...

speedxl

pops the energizing is the magnetic field where talking about .the motor will center where the field is the strongest. and by shimming we attempt to keep the arm were its the strongest when the motor shifts from side to side if were able to see a dyno result in a long graph the line (wave form) would go up and down and you wouldnt get a steeady horspower reading.
your pretty much harnessing the power and keeping it in a linear
power band that is effeciant!

speedxl

pops the energizing is the magnetic field where talking about .the motor will center where the field is the strongest. and by shimming we attempt to keep the arm were its the strongest when the motor shifts from side to side if we were able to see a dyno result in a long graph the line (wave form) would go up and down and you wouldnt get a steeady horspower reading.
your pretty much harnessing the power and keeping it in a linear
power band that is effeciant!

seaball

iTrader: (9)

yeah, we've taken over this thread! the mvp will react the same way that other motors will when zapped. it will have stronger magnets as a result. if it has only a few runs on it, and never got hot, i wouldn't even bother to zap.

i hate to insert my opinion here, but most of us here at the gate (see new gate thread for pics) can't get the performance out of a yokomo (reedy) stocker that we can with the epics (trinity). especially after the release of the monster. i hate it as much as the next guy, but the mvp's are so sensitive to gearing, and just run too hot for most of us. can it be done?? maybe, but it's a much safer bet to tune the trinity motors. i'm just trying to be constructive here, and not start a motor war. $15 for an arm is 1/2 way to a new motor. of course, if you don't race, you may never have a concern, thus, saving $15.

fyi - the mvp has some of the strongest magnets around. 2nd maybe to the orion stocker (which uses the mvp arm)

popsracer

I understand perfectly what everyone is trying to do with the Shimming of the Armature (read my previous posts).

What I was speculating on was:

Does the Center or "Sweet" spot (as some like to call it), change when Current is passing through the Windings of the Armature. Comparing this to, the de-energized spin tests we all do to find center.

speedxl

pops its greater when its energized with current . the magnetic forces cause it to center with out current. i think seaball can give a better explanation i seem not to be able to word it correctly i do understand how it works just cant put it into perspective for you to understand! i tried!

fatdoggy

Mvp - I race with it every weekend and I really like it. Sure it gets hot and is a little gear sensitive, but it can seriously compete with monsters on medium to small sized tracks.

Horatio

Fatdoggy: I Like th MVP too - it's a very quick stocker that seems to offer both good torque and acceptable top speed. It does get hot though, that's a fact, but so long as it's maintained and skimmed regularly the performance remains pretty consistent. Many people get put off by this and believe the motor only suits 2wd or very light weight cars (Pan cars, 1/12th etc). I disagree and just accept it gets hotter than a P2k

Popsracer: The idea you have posed is a valid one - when we observe the arm moving in & out, is this the magnetic field moving around (depending on the applied current) with the arm held in it's magnetic centre? OR is it centrifugal force throwing the arm off the magnetic centre (sweet spot) while the arm is spinning? I can't answer this and had never imagined that the magnetic center could move - I'd always thought this was fixed so long as your magnets weren't cracked or loose I'm sure some physics somewhere can give us the theoretical answer. However, based on the Dyno results mentioned above and the wavey line produced by an unshimmed motor, perhaps this gives us an early indication of what the practical reality is. A straighter line produced by a shimmed motor gives us more consistent power - but was the average output higher or lower?

fatdoggy

Well it looks like the heat has taken it's toll on my MVP, it blew a magnet last night. I rebuilt it and it just didn't run the same, couldn't figure it out till this morning. I'm racing this afternoon and I'll have to get another motor (Mvp if I can get one) and do all the prep work to get it too run decient. This sucks arse!

Horatio

We've all killed motors mate - don't let it get you down! This is why most racers keep at least 1 decent spare motor, just incase one goes bad. Take a chill pill and try again

fatdoggy

Horatio - I managed to get another Mvp (last one in the shop ) after being prep'd it ran just as well as my last one.

speedxl

guys the motors like to run hot just ignore the fact and run them.
at the nationals and before i was running them i would shave of about .010 off of the top and bottom and went with a purple and green springs using e brushes and geared them at 6.80 to 7.10 final drive they were fast didnt get as hot almost the same as a p2k and the perforemance did not taper off towrads the end of the run.try this and let me know if you guys like it. these motors like to wind out and dont like full face brushes i have even done slots east west cust on the faces with good results.

Horatio

Fatdoggy: Glad you got a nice new MVP

Speedxl: Thanks for sharing that motor set up with us; I was having to run 1:8.18 in my TC3 on our fairly tight high-grip carpet track to stop it from reaching 'critical mass' I'll let you know how it works for me with the changes you mentioned. Only thing is, I'll be running it in a Yok SD so won't be able to give a direct comparison. Cheers mate.

speedxl

horatio the gearing i specified for a medium size track with with 60 by 110 foot dimensions our lap times in stock are about high 15's so for genarlly smaller tracks a 7.90 to 8.20 gear ratio would be on the money! good luck!

holycow

you mean a 7.90 to 8.20 roll-out ratio