To BTA, or not to BTA?

[papabash]

Okay guys, I have a GC3 that I have installed true BTA steering on (servo faces backward so everything is behind the axle). I really like it, but I have also noticed that MANY of the top drivers don't do BTA on their 1.9's. I have a moonbuggy ordered, and want to do it up right (I will keep both rigs, but the moonbuggy will be my primary comp rig). What are your opinions on whether to run BTA or not, and if not, WHY NOT? Just trying to understand both sides so I can decide which to do. Thanks.

[rock hard]

If you can run the srvo fliped I'd stick with it like that for a while.
Drive some stuff to test with.
Deep v cracks,drive up ledges with an overhange ect.
Then flip the srvo back out front,drive the same lines.
See for yourself which one is best.

The servo horn is the only thing I'v ever hung up on really.

You can actually use wax on the servo,and on the steering link to help it slide.

But the servo horn just digs in

[JeremyH]

IMO, to get the full benefit of BTA on this truck, you need to run a low profile servo....but good luck finding one with decent torque. I run a Futaba S9551 and it does not stick out past the front of the axle. This servo only puts out about 140 oz-in of torque. I run the RCBros front servo mount. I did have to raise the servo up slightly to get full throw and clear the link mount.

I am quite happy with my setup:

[papabash]

My servo does stick out a bit in front of the axle, and I had been wondering about a low-profile servo with decent torque. I'm like you, though Jeremy, I need to raise the servo just a tad for better clearance (it works, but hits just a bit), but then I'm raising the COG. I also like some of the OTA setups I've seen lately , but if the horn and drag link are still out front, I have trouble seeing a huge benefit. Wish there was enough room to do a Ripper7 style setup on these!

[86jeep]

Very nice and clean Jeremy.
But people need to remember like anything there's always a trade off when we mod something. You got everthing BTA but you had to raise the servo. You gained one thing BTA but lost two other thing's. You have a higher CG now by raising the servo. I lowered my servo from the stock location down to where it rest on the axle now and gained 3 degree's on the vert ramp. Second by raisng the servo the servo will rest on the ground when your on your lid and it make's it super hard next to impossable to up right the truck on it's own. Maybe the BJ is differant im just going off my testing with my old GC3 and my new T1e moonbuggy.

[rock hard]

Originally Posted by 86jeep

Very nice and clean Jeremy.
But people need to remember like anything there's always a trade off when we mod something. You got everthing BTA but you had to raise the servo. You gained one thing BTA but lost two other thing's. You have a higher CG now by raising the servo. I lowered my servo from the stock location down to where it rest on the axle now and gained 3 degree's on the vert ramp. Second by raisng the servo the servo will rest on the ground when your on your lid and it make's it super hard next to impossable to up right the truck on it's own. Maybe the BJ is differant im just going off my testing with my old GC3 and my new T1e moonbuggy.

You know Greg,its good to see you posting over here,the advice is much appreciated by all

[86jeep]

Originally Posted by rock hard

You know Greg,its good to see you posting over here,the advice is much appreciated by all

[JeremyH]

Originally Posted by 86jeep

Very nice and clean Jeremy.
But people need to remember like anything there's always a trade off when we mod something. You got everthing BTA but you had to raise the servo. You gained one thing BTA but lost two other thing's. You have a higher CG now by raising the servo. I lowered my servo from the stock location down to where it rest on the axle now and gained 3 degree's on the vert ramp. Second by raisng the servo the servo will rest on the ground when your on your lid and it make's it super hard next to impossable to up right the truck on it's own. Maybe the BJ is differant im just going off my testing with my old GC3 and my new T1e moonbuggy.

Thank you. And yep, I completely agree. Everything has a pro and con. Having the servo in that position is certainly not ideal and I am always on the lookout for a way to lower it. For the types of courses we have down here (with lots of holes and few straight, steep climbs), this setup seems to work better for me than having the steering links out in front.

[86jeep]

Originally Posted by JeremyH

Thank you. And yep, I completely agree. Everything has a pro and con. Having the servo in that position is certainly not ideal and I am always on the lookout for a way to lower it. For the types of courses we have down here (with lots of holes and few straight, steep climbs), this setup seems to work better for me than having the steering links out in front.

You said the magic words "For the types of courses we have ". Thats the most important thing.

[RickM]

Seams to me that what it all comes down to is approach angle. I like and agree with what Greg is saying as the increase in terms of climbing degree however it might have me rethinking my front setup now. I simply raised up my linkages as it is now but dropping the servo some sounds like a really good idea.

[RcBro]

As mentioned BTA is hit or miss. There are tons of things to take into account when running a BTA versus a OTA or even the stock setup. Your servo, knuckles, shocks, chassis and servo mount all affect how your setup will work. What works on one rig probably wont work on another unless compeltely identical.

I have spent hours working on different geometry setups with my mini. I've bent and threaded stainless rod until my noes bled. (not really but you get the idea) Each time testing the effectiveness of the setup.

It took me forever to find a setup that kept the center gravity low and gave FULL steering throw in each direction without hindering anything. I have finally found something that works great with my MRC pro, but probably mine only. I tried thinking out of the box, and ended up just rocking a basic setup which I have found to work really well. I hope to update my mrc thread soon.

[JeremyH]

Well, this thread got me staring at my BTA setup and here is the result:



Same BTA clearance as before, and now the servo sits on the plate with no gap.

[papabash]

Looks good Jeremy! I couldn't tell from your picture above, but we came up with basically the same setup for our rigs. My drag link is on the opposite side and bent, but other than that, they look very similar.

[JeremyH]

Yep, they look very similar. Nice work!

BTW, Fastener Express sells some aluminum button head screws that are the same size as the diff case screws (at the corners of the pumpkin).....they are a bit less of a rock grabber than the stock socket head screws. You can see them on my pictures above.

[rock hard]

Why didnt you think of that before Jeremy?

Looking good,the cheapest improvments are my favorites!

[JeremyH]

Originally Posted by rock hard

Why didnt you think of that before Jeremy?

Because I was using the servo posts on my berg....but took them off the other day to reconfigure that steering. Now, both are working quite well!

[papabash]

Originally Posted by JeremyH

Yep, they look very similar. Nice work!

BTW, Fastener Express sells some aluminum button head screws that are the same size as the diff case screws (at the corners of the pumpkin).....they are a bit less of a rock grabber than the stock socket head screws. You can see them on my pictures above.

Thanks, I've been meaning to find some, just hadn't got around to it yet. Now that I know right where to look, I'll get on it.