2Likes17.5 tips and speed secrets
08-17-2016, 11:00 AM
#183
anyone try the proline lite 2.2's? just got a set in the mail. they feel very similar to a regular 2.2, but a couple grams lighter. nothing at all like the brick hard 2.4's.
08-17-2016, 11:07 AM
#184
Let's suppose we are talking about packs built with the same technology and materials.
Amps can be safely considered the same, resistance is inversely proportional to cell size. mAh value is linearly proportional to cell size.
It means voltage drop caused by load is higher with smaller cells/packs, and after the same amount of mAhs drawn they will also be further down the working voltage curve.
These two factors both work in the favor of bigger packs, in this case the saddles.
08-17-2016, 11:21 AM
#186
It's quite simple. Voltage drop = Amps drawn by motor * internal resistance of the battery.
Let's suppose we are talking about packs built with the same technology and materials.
Amps can be safely considered the same, resistance is inversely proportional to cell size. mAh value is linearly proportional to cell size.
It means voltage drop caused by load is higher with smaller cells/packs, and after the same amount of mAhs drawn they will also be further down the working voltage curve.
These two factors both work in the favor of bigger packs, in this case the saddles.
Let's suppose we are talking about packs built with the same technology and materials.
Amps can be safely considered the same, resistance is inversely proportional to cell size. mAh value is linearly proportional to cell size.
It means voltage drop caused by load is higher with smaller cells/packs, and after the same amount of mAhs drawn they will also be further down the working voltage curve.
These two factors both work in the favor of bigger packs, in this case the saddles.
socket brings up a good point with battery chemistry. the shorty's that we use are generally designed for stock racing and offer the lowest IR's available. there's no need for this with saddle packs as they are generally used for mod racing. from his experience, shory's also react better to high charge/discharge procedures.
not so "simple" as you state. i'll stick with my shortys.
08-17-2016, 11:33 AM
#187
Everyone else here is providing good discussion depending on what they're opinion of saddle vs shorty is but you just respond with know-it-all replies like "oh gee that don't apply to me" and "oh you don't know what ur talking about" "I've tried it, I've mapped it". You should probably just stop typing, admit you don't know everything and try to learn something on here.
08-17-2016, 12:50 PM
#188
I think you just want the r/c world to know you're a bad ass and you discharge/charge your batteries at extreme amperages since you figured it out a couple weeks ago.
Everyone else here is providing good discussion depending on what they're opinion of saddle vs shorty is but you just respond with know-it-all replies like "oh gee that don't apply to me" and "oh you don't know what ur talking about" "I've tried it, I've mapped it". You should probably just stop typing, admit you don't know everything and try to learn something on here.
Everyone else here is providing good discussion depending on what they're opinion of saddle vs shorty is but you just respond with know-it-all replies like "oh gee that don't apply to me" and "oh you don't know what ur talking about" "I've tried it, I've mapped it". You should probably just stop typing, admit you don't know everything and try to learn something on here.
If you dont like my posts, you have two options. Put me on ignore, or ask for a refund on your membership.
I'm here to spread ideas and give some insight in what the top 1% of 17.5 racers are doing and how. I understand I'm brash and forward, sometimes it even hurts people's feelings, however I urge you to stop being offended like everyone is today and read in to what I'm saying.
You can't just post randomized discharge data and not post the information about the parts I specified. I've tried my best to elaborate and provide scientific backing to why a high discharge rate and high charge rate matter, but it isn't that easy.
The difference between me and most? I'm not afraid to try something. Other than the team powers 17.5, I've owned every "certified" or team motor on the market today. Some I've had to purchase myseld, some were given for testing, and some I've had to return.
Right now I literally have $800 in 17.5 motors sitting in my box. There's a reason I get 10 pm's a day asking for racing and equipment advice, because I've experienced it. I'm also not afraid to admit when I'm wrong or don't know something. I think I have 15 lipo's in my ammo box, all have a label and a notebook corresponding to their cycles and usage.
Some people don't like me, that's fine, this isnt a popularity contest, this is racing.
I'm the guy when something new comes out I buy it and try it. If it doesn't work, I work on it to see if I can make it good. If I can't get it there, I either trash it or sell it.
08-17-2016, 01:17 PM
#190
For gearing I don't care at all about temps, the car should be light enough with light enough drivetrain as well as a strong fan to never get warm.
I usually start at 31x72 on the b6 and work from there. I gear by feel and visual speed. If the car stops pulling right off the corner then I know I'm under geared, and if it still pulls on the end of the straight away, then I know I need to go down .
I don't stop there though. I am constantly making changes to gearing until I've absolutely found the sweet spot. If I feel like I'm in between pinions, I'll go with the smaller pinion and bump timing by 5 degrees and see what that does. Gearing is something you should never settle with.
08-17-2016, 01:26 PM
#191
So a certified or team motor has "what" done to it that an analyzer would not help with? Or is my interpretation of what he is using it for wrong? He was using it for finding a higher amp draw by changing end bell timing, his theory is to find close to a 6 amp draw and then gear from there. I'm new to the 17.5 game so excuse any ignorance.
08-17-2016, 01:36 PM
#192
No worries. You're on the right track.
When it comes to the fantom works or the motiv and trinity, they've done the work for you. When it comes to say an off the shelf Reedy, you need to do the work to find the sweet spot.
I'm not completely enthralled on short stack motors for offroad, and even more so for carpet or astro. They die for rpm, and regard less of ceramic bearings and a light drivetrain, you can only make the car so efficient. This seems to stress the very pesky short stacks in my experience.
This is where tracks with wheel spin are interesting because of its impact on rpm, and then gearing. This is why you can't suggest gearing over the internet, and can't suggest a motor without seeing the track or knowing the car.
Edit: yes, I left schurrspeed out for 2 reasons: they were caught cheating at cactus, and when I motor Ron and his team driver, I know they're not on the right track.
When it comes to the fantom works or the motiv and trinity, they've done the work for you. When it comes to say an off the shelf Reedy, you need to do the work to find the sweet spot.
I'm not completely enthralled on short stack motors for offroad, and even more so for carpet or astro. They die for rpm, and regard less of ceramic bearings and a light drivetrain, you can only make the car so efficient. This seems to stress the very pesky short stacks in my experience.
This is where tracks with wheel spin are interesting because of its impact on rpm, and then gearing. This is why you can't suggest gearing over the internet, and can't suggest a motor without seeing the track or knowing the car.
Edit: yes, I left schurrspeed out for 2 reasons: they were caught cheating at cactus, and when I motor Ron and his team driver, I know they're not on the right track.
08-17-2016, 02:10 PM
#193
I've so over the "One wreck and none of this stuff matters" cliche. I'm pretty sure the guy who asks these questions are already fully aware of this actuality, and didn't post to get mocked. While there's a 100% truth in the cliche, even the best racers in the world wreck. I just watched the 6 2w and 4w buggy Nationals Amains on youtube and saw a lot of marshaling. Phend put on one of the greatest displays of RC talent you'll ever see, and he wrecked 3/4 times.
When I'm racing 17.5 buggy, most of my wrecks are either dealing with slower cars or big jumps, or catching a tube cause I'm try to use all the track. Having that extra .1 or .2 per lap that all these trick parts and expensive electronics/chargers 'might' provide could be the difference in me clearing the big double cleanly 13/15 times or 15/15 times. It could be the difference is a slower driver making a higher main and having a successful weekend. So there is value in this even if your not a word class driver like Socket (jk Socket, you're cool).
When I'm racing 17.5 buggy, most of my wrecks are either dealing with slower cars or big jumps, or catching a tube cause I'm try to use all the track. Having that extra .1 or .2 per lap that all these trick parts and expensive electronics/chargers 'might' provide could be the difference in me clearing the big double cleanly 13/15 times or 15/15 times. It could be the difference is a slower driver making a higher main and having a successful weekend. So there is value in this even if your not a word class driver like Socket (jk Socket, you're cool).
08-17-2016, 02:15 PM
#194
What happened at Cactus? Ive watched some of the Ron Shurr interview with Jconcepts and he seems like a knowledgeable dude and a RC junkie/nerd. Ive never owned a Schurrspeed motor, Are they any good? Not that it matters, I'm planning on getting a Fantom stocker for this season.
08-17-2016, 02:20 PM
#195
Yes I totally get that point. I'd prefer to not but an analyzer for just 17.5 racing. So "generally" speaking whats a good out of the box 17.5 for stock buggy carpet racing, smaller track. Price is not much of an issue, I dont mind paying for quality products.