K8exb gearing

[torc]

Just picked up a castle xlx2 1100kv (sensored) motor for my K8exb only pinion i could find with an 8mm bore is a limitless 34t should i run 34/47 or 34/39 with the optional spur anyone with experience with this combo and car that could help would be appreciated

 

[Moirae]

I don't have that combo but I do have an xlx2 + tp 1270 kv and I run 31/39. considering the kv difference I'd assume you'd be able to handle 34/39 with some fans. Might be smarter to start 34/47 and see how you like it first though. Go to sagacustom and get some more pinions =P

 

[Matt05]

34/39 will get hot for sure. Currently I’m running a saga 30t pinion with the 39t spur. Still gets hot pretty fast so I ordered a pps motor slider to be able run a saga 34t pinion with the factory 47t spur.

 

[torc]

34/39 will get hot for sure. Currently I’m running a saga 30t pinion with the 39t spur. Still gets hot pretty fast so I ordered a pps motor slider to be able run a saga 34t pinion with the factory 47t spur.

34/47 doesn't fit the stock mount went with 34/39 after 20 min running im only seeing temps of 140f with dual sky rc fans but on 100% throttle im cutting out due to my voltage dropping below lvc seeing large voltage spikes on my b-link gona lower my pinion size maybe some better higher c rating batteries

 

[Matt05]

34/47 doesn't fit the stock mount went with 34/39 after 20 min running im only seeing temps of 140f with dual sky rc fans but on 100% throttle im cutting out due to my voltage dropping below lvc seeing large voltage spikes on my b-link gona lower my pinion size maybe some better higher c rating batteries

Yeah I had to switch to the pps motor slide deal to accommodate 34/47 gearing.

 

[a2lowvw]

Have a couple buddies running the same setup 34/39 with the cc 1100kv/xlx2. They run big fans to keep them cool. They also run qs8 connectors and big batteries.

 

[torc]

lowered my pinion to a 29 running 29/39 still having hesitation at 100% throttle thinkin i need a higher discharge higher c ratied battery currently just eunning cheepo youme 6200mah 50c data log show during full throttle im dipping below lvc

 

[Moirae]

lowered my pinion to a 29 running 29/39 still having hesitation at 100% throttle thinkin i need a higher discharge higher c ratied battery currently just eunning cheepo youme 6200mah 50c data log show during full throttle im dipping below lvc

I have a very similar problem and I've yet to figure it out. Sometimes it doesn't happen, and I think I fixed it and then it just comes right back.

 

[torc]

Problem solved plenty of punch and capacity

 

[Moirae]

Problem solved plenty of punch and capacity

View attachment 231996

What batteries did you use before? and this totally fixed it?

 

[torc]

Had some youme 6200mah 50c amzon special lol had to turn down all my setting with these batteries tried these out yest turned all my setting back up to 100% not a single problem no cutouts even at full throttle for extended periods no problem everything stayed nice and cool to highly recommend

 

[torc]

Some #s from my test and tune 10 min straight full throttle street rips 29/39 gearing cc 1100kv xlx2 sky rc dial40mm fans

 

[torc]

Some more #s

 

[Onnexx]

Jeez i don't know how you guys are running these gearings and not frying everything. Was running a max5 and 1100kv hobbywing on 29/47 and it was getting hot all the time(granted florida but still) switching to lower kv motor gave better acceleration and cooler temps while,somehow, running quieter. kudos to you guys for even trying.

 

[Moirae]

Jeez i don't know how you guys are running these gearings and not frying everything. Was running a max5 and 1100kv hobbywing on 29/47 and it was getting hot all the time(granted florida but still) switching to lower kv motor gave better acceleration and cooler temps while,somehow, running quieter. kudos to you guys for even trying.

Haha I just got an o8s recently and I put in a max5 + TP5660 1356kv and I have it geared 31/47 with 2x 40mm alu frame fans and it's great. I was actually amazed by the temps tbh. I've only done wheelies and rips up and down the street pretty much nonstop but definitely impressed. Crazy considering my KV is higher than what most people run.

 

[abh16]

Is there a good tutorial on gearing that you guys recommend? Reading all these options 39t vs 47t etc make my head explode! Is there a gearing for dummies?

 

[torc]

Try this is what i used has different ratios kv,s and speeds https://docs.google.com/spreadsheets/d/172JeLv4pGQYZ2fq2hMav_jhvPy5RMOYb2kBpuxgyUeY/edit#gid=0

Is there a good tutorial on gearing that you guys recommend? Reading all these options 39t vs 47t etc make my head explode! Is there a gearing for dummies?

https://docs.google.com/spreadsheets/d/172JeLv4pGQYZ2fq2hMav_jhvPy5RMOYb2kBpuxgyUeY/edit#gid=0 check this out
Pick your kv and gear ratio and it tells u est.speed pretty acurate

 

[abh16]

Yeah I had to switch to the pps motor slide deal to accommodate 34/47 gearing.

When you guys say the pinion doesn't fit what that mean? What is exactly the problem? Is it with the motor lengtWh or width? What pinion sizes do and don't fit? Is there a quick rundown on this?

 

[Matt05]

When you guys say the pinion doesn't fit what that mean? What is exactly the problem? Is it with the motor lengtWh or width? What pinion sizes do and don't fit? Is there a quick rundown on this?

Should be in your manual. I believe @Jon NC RC posted a picture of it somewhere.

 

[abh16]

The manual states to do that you must first look up the motors gear ratio but that's not provided by Castle!