REVO 2.5 will many upgrades and just as many questions.

[Traijin]

I recently purchased a REVO 2.5 off Ebay. I got what I paid for. 2.5 chassis with a Picco .26 Maxx. Piggy Back Shocks, aluminum A Arms, roll cage... blah blah blah. I am new to RC, but I have extensive experience with mechanical things, I served as Pitcrew for AMA Supercross and Motorcross for a few years and AMA Super Sport, Super Stock, and Super Bike for 3 years. So, I understand all the principles of suspension setup and two stroke motor tuning and adjustment. This RC will be used for "bashing" I just want to run around and have fun with it. On Saturday I stripped it down to the chassis to inventory the broken/bent parts. This activity yielded several questions I would like some help on.

1) Are there any benefits to converting from a 2.5 chassis to a 3.3 chassis? I understand the 3.3 is a bit longer, but is that dimension change reflected in the wheel base? I could see how adding an inch or so helps if the wheel base is extended. I have already priced the chassis, steering linkage, half shafts, and center brace, is there any real world benefit to control and handling?

2) The screw boss for the battery box/opti box to the lid is stripped. I need to replace the box. If I upgrade to a 3.3, is there any benefit to upgrading to the 3.3 battery box/opti drive configuration?

3) This truck's drive shafts were a mess, 3 stock plastic and 1 CVD. I have priced the Traxxas CVD's. Should I be looking at after market CVD's? What MFG?

4) When switch to CVD's do I need different sockets at the differential? On the one CVD on my truck there is a socket instead of a U Joint.

5) Currently the truck has long travel rockers installed. I do not intend to do any rock crawling, is there real benefit to that much suspension travel? One of the rocker's screw boss is stripped out. It has to be replace. I need to decide whether to stick with long travel or go to a progressive 2. Logic would lead me to longer travel equals more leverage and more breakage of parts. Is that assumption correct?

6) The push rods and turn buckles were mostly bent, I will replace them all. If I go with progressive 2 rockers, is there any reason to get lengths of the rods outside of stock? I went to the hobby store and saw many different lengths. What is the stock MM length? Is it is wise to stick with that size?

7) The truck came with a dual exhaust pipe. The header is bent and causes a restriction. This is unacceptable. Makes for bad exhaust leaks too. Anyway, I understand the principles of the pipe using reflection for compression. On a 125 or 250 cc motor this reflection was a product of two counter opposed cones of varying lengths to adjust the powerband. I am looking for mid range torque/horsepower. I prefer the energy be usable. So extreme high end or low end do not matter to me. What is a good pipe for a Picco .26 maxx for mid range torque/horsepower?

8) I just picked up dynamite medium glow plugs, does anyone else have glow plugs they prefer for a Picco 26 Maxx?

9) I enjoy Wheelies for about 30 seconds, after that I would prefer to put the power to use. For "bashing" is a center differential applicable? Or are those benefits usually only expressed at the track?

10) The truck came with a complete, but uninstalled sway bar kit. I looks easy enough to install. Are there real world benefits to controlling body roll whilst "bashing" It seems like a good idea to me. Are there any nasty trade offs after installing a sway bar kit? Fitting the body? New stress points on the suspension?

Thanks for any input. I Appreciate the help.

I look forward to building this truck this winter. I already have RPM front and rear kit on order. I look forward to shedding a pound or two from the other miscellaneous things I will shave. But I think this truck will be a lot of fun this spring.

Thanks again,

Traijin

 

[hamz9561]

1. The longer chassis makes for better handling. It helps keep all four tires planted under most circumstances.

2. There is no real difference between the 2 chassis with regard to the battery/opti-drive box.

3.Traxxas does make CVDs. A company that I've had really good luck with using is MIP. Here is a link to both types of CVD sets:
Center: http://www.amainhobbies.com/product...products_id/8556/n/MIP-Center-CVD-Kit-Revo-33
Front or Rear http://www.amainhobbies.com/product...id/8554/n/MIP-CVD-Kit-Front-Rear-Revo-Maxx-33

4. Usually the CVDs are mad to fit the existing connectors. If they need a conversion kit they usually come with it.

5. They make 3 different sets of rockers for the Revo. The long travel rockers are used for heavy terrain and jumping.

6. I believe that the pushrods are 120mm.

7. Ditch the dual outlet exhaust. They are hard to tune and don't tend to help out the power. Get the big block header from Traxxas and use a THS pipe. These pipes are loud, but make loads of power across the band.

8. Usually I found that using the McCoy;'s medium plugs with 30% fuel.

9. I am not a racer but really like the center diff. It allows for better cornering at speed. It allow you to use the rear brake set up which gives better braking performance and allows you to set the braking bias to your preference. Adding this will also make the transmission stouter and remove the troublesome opti-drive and reverse.

10. I haven't played with the sway bars on my Revo, but I have used them on other vehicles and I noticed that I needed softer springs and less pre-load.

If your truck came with Integy brand piggybacks, throw them away and get the Traxxas Titanium Nitride shocks. Integy has poor material quality control and no customer support. If you convert to the 3.3 chassis, that will help reduce the wheelie tendencies of the shorter chassis. The drawback to this is you will have to replace the roll cage and body that came with your truck.

Enjoy your truck!

 

[Traijin]

Excellent, Thanks! Appreciate the help.

Traijin

 

[revo_rob_1984]

well first off congrats on your find, and second if those shocks are integy GET RID OF THEM NOW!!!!. . . they are garbage yeah they look cool, but thats about it. I highly suggest you upgrade your radio system to a 2.4 ghz setup (spektrum DX3S, Futaba FAAST ect) and ditch that optidrive, all optidrive does is cause problems, granted yeah its a good thing to have if you don't know how to stop and put your rig in reverse, but all of us know that you need to stop and put it in reverse any wayz. . .you wouldn't throw you real car in reverse at 30 mph now would ya. . .no i didn't think so. . .sorrry for sounding like a smart @$$. . .but seriously. . .and there is a benifit for the 3.3 chassis over the 2.5 chassis. . .the 3.3 is longer so you will have a longer wheelbase and it will be less apt to going into a wheelie still possible but not all the time like it would be with the 2.5, and the dual exaust is not good for a nitro motor, good for a shelfqueen that you are just going to stare at but never run, i can't remember what pipes people are using but i personally am using the TRX single chamber tuned pipe and i have no complaints about it. as far as pushrods and toe links i would just go with the red anodized ones because 1. they are stronger, and 2. they just look better and if you plan on jumping it 30 feet in the air(exaggeration), stick with the long travel rockers, but if you are just gonna bash it and occasoinally jump it 6 or so feet in the air or over a car P2 rockers are just fine, thats what i have and i rebuilt my shocks with 40WT oil all the way around and i jumped over my car (hood to trunk) and hit the ground and kept right on going it was probably 6-8 ft in the air and it probably went 15 or so feet so the p2's are plenty good enough. The CVD-s i wish i could answer that one for you i have the stock shafts on mine and all i did was rebuild them and now they are fine i would just stick with those the metal ones are expensive and add weight, if i ever break one of the plastic ones i will go with metal but until then i will stick with plastic. I use O.S. #8 plugs in my picco .26 Maxx and 20% nitro fuel and i have power to spare. I hope i have helped answer some of your questions and i really hope i didn't confuse you.

 

[Traijin]

So after more reading, it looks like there is no question about the long travel rockers... it looks like I cannot use them in conjunction with RPM A Arms, so that settles that.

Hamz9561, I like the Mip CVDs, it looks like a quality build. You also recommended A Traxxas BB header and a THS pipe. I looked at the pipe on Tower Hobby, looks like the pipe for a REVO comes with a header. Is the Traxxas BB header better?


Revo_Rob, Yeah, looks like I plan to install the center diff, rear brake, and forward only conversion... this will render the opti useless... so I agree, who cares about shifting into reverse Does the 2.4 GHz offer more range? Reliability? Both? Why the up grade?

Thanks for the help folks.

 

[syphon68]

Does the 2.4 GHz offer more range? Reliability? Both? Why the up grade?

The stock Radio is AM 27 mhz and is prone to interference and range issues because it uses crystals and it is a shared channel so if anyone else around you is using that channel your rig will twitch or even worse take off and hit something. 2.4 ghz will give you a dedicated link between you and the RC that will provide interference free operation and it is more precise just because of the higher bandwidth channel. Your 2.4ghz radio options really depend on your money available and what you are going to do with the RC. I bought a cheap $80 Tactic 2.4 ghz radio for my sons Rustler and I love it, I haven't had a problem at all with it but it doesn't have the same precise adjustments and feel as my Spektrum DX3S $240.00 and I haven't really looked into the higher end radios. Either way even the Tactic radio was a huge upgrade over the stock and well worth the $$$.

 

[revo_rob_1984]

Does the 2.4 GHz offer more range? Reliability? Both? Why the up grade?

It does both it has much MUCH better range and the reliability is second to none with a 2.4GHZ setup. I upgraded to the Spektrum DX3S because i wanted good sport radio with the features i was looking for, 2.4 GHz, and telemtery, it will tell me engine speed, engine temp, rx battery life, run time and it has a 10 Model memory on it so if you have 10 rigs with 10 spektrum recievers you can run them all off of the same Transmitter (not all at the same time obviously, the only reason i say that is because someone asked me "how do you control all 3 of your rc's at the same time") Needless to say i completly ignored that question.

 

[Traijin]

the only reason i say that is because someone asked me "how do you control all 3 of your rc's at the same time") Needless to say i completly ignored that question.

Thanks, that is reasonable given the fact that I intend to pick up a Nitro boat this summer. I am also a big fan of telemetry.

 

[revo_rob_1984]

Thanks, that is reasonable given the fact that I intend to pick up a Nitro boat this summer. I am also a big fan of telemetry.

The DX3S can control your boat too. . .as long as you have the spektrum Marine reciever

 

[hamz9561]

Either header should work with the set up that you're looking at.

 

[2revo1maxx]

I recently purchased a REVO 2.5 off Ebay. I got what I paid for. 2.5 chassis with a Picco .26 Maxx. Piggy Back Shocks, aluminum A Arms, roll cage... blah blah blah. I am new to RC, but I have extensive experience with mechanical things, I served as Pitcrew for AMA Supercross and Motorcross for a few years and AMA Super Sport, Super Stock, and Super Bike for 3 years. So, I understand all the principles of suspension setup and two stroke motor tuning and adjustment. This RC will be used for "bashing" I just want to run around and have fun with it. On Saturday I stripped it down to the chassis to inventory the broken/bent parts. This activity yielded several questions I would like some help on.

1) Are there any benefits to converting from a 2.5 chassis to a 3.3 chassis? I understand the 3.3 is a bit longer, but is that dimension change reflected in the wheel base? I could see how adding an inch or so helps if the wheel base is extended. I have already priced the chassis, steering linkage, half shafts, and center brace, is there any real world benefit to control and handling?

2) The screw boss for the battery box/opti box to the lid is stripped. I need to replace the box. If I upgrade to a 3.3, is there any benefit to upgrading to the 3.3 battery box/opti drive configuration?

3) This truck's drive shafts were a mess, 3 stock plastic and 1 CVD. I have priced the Traxxas CVD's. Should I be looking at after market CVD's? What MFG?

4) When switch to CVD's do I need different sockets at the differential? On the one CVD on my truck there is a socket instead of a U Joint.

5) Currently the truck has long travel rockers installed. I do not intend to do any rock crawling, is there real benefit to that much suspension travel? One of the rocker's screw boss is stripped out. It has to be replace. I need to decide whether to stick with long travel or go to a progressive 2. Logic would lead me to longer travel equals more leverage and more breakage of parts. Is that assumption correct?

6) The push rods and turn buckles were mostly bent, I will replace them all. If I go with progressive 2 rockers, is there any reason to get lengths of the rods outside of stock? I went to the hobby store and saw many different lengths. What is the stock MM length? Is it is wise to stick with that size?

7) The truck came with a dual exhaust pipe. The header is bent and causes a restriction. This is unacceptable. Makes for bad exhaust leaks too. Anyway, I understand the principles of the pipe using reflection for compression. On a 125 or 250 cc motor this reflection was a product of two counter opposed cones of varying lengths to adjust the powerband. I am looking for mid range torque/horsepower. I prefer the energy be usable. So extreme high end or low end do not matter to me. What is a good pipe for a Picco .26 maxx for mid range torque/horsepower?

8) I just picked up dynamite medium glow plugs, does anyone else have glow plugs they prefer for a Picco 26 Maxx?

9) I enjoy Wheelies for about 30 seconds, after that I would prefer to put the power to use. For "bashing" is a center differential applicable? Or are those benefits usually only expressed at the track?

10) The truck came with a complete, but uninstalled sway bar kit. I looks easy enough to install. Are there real world benefits to controlling body roll whilst "bashing" It seems like a good idea to me. Are there any nasty trade offs after installing a sway bar kit? Fitting the body? New stress points on the suspension?

Thanks for any input. I Appreciate the help.

I look forward to building this truck this winter. I already have RPM front and rear kit on order. I look forward to shedding a pound or two from the other miscellaneous things I will shave. But I think this truck will be a lot of fun this spring.

Thanks again,

Traijin

No problem with traxxas cvd's. They aren't quite as good as mip but they're much lighter and look bad ass. The suspension leverage is not really an issue but stock rear rockers will break and shocks will eventually bend slightly, also too many wheelies will pull plastic rod ends apart. For pushrods you can shop around there's two kinds, one set is for pro 3 rockers and the other is for pro 1 and 2. with pro 2 you add spacers to make them longer. Get a THS pipe I've seen how they can wake up a 3.3 they're awesome, plus they're spring mount, no more bent manifolds. Lastly, the extra 30mm of chassis makes a world of difference.

 

[Traijin]

So, as an update... I have ordered the following:

1) 3.3 Chassis, brace, and half shafts.
2) Titanium Nitride Shocks
3) Pro 2 Rockers
4) RPM True Track rear kit and front A arms
5) Traxxas CVDs
6) Aluminum Toe links for the front


I have already bought and installed the center differential and removed the optidrive along with the reverse gearing. I bought the sway bar kit and rear brake kit. Installed a hardened clutch bell. The truck already had an after market flywheel and 3 shoe clutch. The truck is stripped down to assemblies and cleaned. Just waiting for the delivery and reassembly.

Since I yanked the Optidrive, wouldn't it be a good idea to install a failsafe? What is a recommended mfg?

I may have spend about the same as buying a platinum 3.3, but I got a Picco .26 and a stock of other parts. But most importantly, I got to take it all apart and learn all the assemblies. It will help when I start breaking things in the Spring.

Now I need to start researching the controllers and decide on a spectrum.

Thanks for the help thus far.

 

[2revo1maxx]

A failsafe is always a good idea. And a 2.4ghz radio of any brand is a wonderful thing too.

I would also get some proline bowtie or badlands tires on dish wheels, 1/2 inch offset to make it wider. Whatever tire you go for keep the tire width relatively narrow for racing. Too wide and you'll be sliding around too much....you knew that though, I'm sure.

 

[Traijin]

No, I can't claim I knew anything of the sort about tire spreads, my knowledge base is motorcycles, this is new to me and I appreciate all the info for sure.

As for tires... the truck can with some bow ties mounted on aluminum wheels with a fake rotor for show. They also have a titanium bead lock. I think the wheels are heavy. Since they are beadlocked, I may look into pilling the tires and putting them on dish rims. Seems sensible and lighter.

I am itching to get wrenching!

 

[Metalhead Matt]

Heavier wheels have their advantages/disadvantages. They can make for a more planted vehicle; = more traction. But the unsprung weight is a little harder on components such as carriers and turnbuckles, ect... Having a separate set of lighter wheels/tires would be a good idea to compare the different handling characteristics and see what works for you. Besides, there's no such thing as too many tires!

 

[2revo1maxx]

Yeah I love building. Especially in western new york this time of year. One thing I forgot about the true track setup....watch the aluminum pivot ball caps, they are a real pain to get started in their threads. It just takes patience, but at least the rpm nylon is very forgiving. I've got 'em on my maxx and revo I couldn't imagine not having them. Also if racing is your goal the dish wheels are pretty much the way to go. Look on proline's website in the bodies section you'll see what they look like. I ended up getting integy wheels and tires for mine, I couldn't turn 'em down for 35 bucks(all four tires/wheels). They look bad ass and are light, it's just that they are wider than alot of other stuff and they might be going on my other revo if I don't like them.

 

[Traijin]

Yeah, I got the true track caps on... delicate procedure for sure. Putting the dust boots on the pillow balls and screwing them in is a royal PITA. Rear brake kit is installed. That was easy enough. The tool I am glad to have thus far is a dental pick set. The picks are perfect for removing bearings, adjusting dust boots, and removing circlips. After I finish this build I will probably post a first timers recommended thread.

 

[2revo1maxx]

Yeah, I got the true track caps on... delicate procedure for sure. Putting the dust boots on the pillow balls and screwing them in is a royal PITA. Rear brake kit is installed. That was easy enough. The tool I am glad to have thus far is a dental pick set. The picks are perfect for removing bearings, adjusting dust boots, and removing circlips. After I finish this build I will probably post a first timers recommended thread.

Yeah a little patience goes a long way with the true track, but it's an awesome setup. I'd be bummin without 'em on my maxx and revo.

 

[Metalhead Matt]

A tap wouldn't hurt for the pivot ball cap threads. I know what you guys mean. I lay 'em flat on the bench and run them in and out before anything else.

 

[Traijin]

This has been a long row to hoe, but I am closing in on it.

So far, I took a junked out 2.5 with a Picco 26 Max and installed:

A 3.3 Chassis, Brace and Half Shafts
GTR Ti Shocks
Traxxas CVDs
RPM True Track Rear set
RPM Front A arms and pivot caps
Aluminum Front Toe Links
Aluminum Front and Rear Push Rods
Center Differential
Rear Brake Kit
Water Proof Digital Throttle Servo
Waterproof Digital Steering servo, single
Motor Saver High Flow Air Filter
Hardened Clutch Bell
Hardened Spur Gear
Replaced any missing fasteners
Added a Traxxas Wing

Still waiting on new shock mounts, the truck had Integy mounts on it, they do not allow the roll bar kit to be installed. Also waiting on a THS Pipe.

I have begun to setup the truck for ride height. I am happy with the front end... green springs with pro 2 rockers. I may move down to stock springs, but this is a basher. I have silver springs in back. The rear ride height is where I want it, but it still bottoms out to fast for my liking. I do not want a heavier spring as it would change the ride height. Does anyone know the stock weight oil in GTR Ti Revo rear shocks? Is it 40 weight? If so, I'm am thinking on moving to 50 or 55 weight if I can find it.

I did paint my first body this weekend. It is a Proform Hard Drive. I found putting a mask on the hood with all the vent like stuff to be very difficult, even with a hairdryer to warm up the vinyl. Anyway it is painted, and since it is my fist body, I am not embarrassed in the slightest.


Been fun so far!