PRP Swift

[SparkyMaxx]

Wil,
Sweet Bodies dude... I don't even want to know what you charge...

Those are HOT though, Very nice work...

 

[HIREz]

Thanks,
Most bodies are 75.00 bucks including the body, plus 10 bucks priority shipping back to ya.

-Will-
www.WilzWerx.com

Originally posted by SparkyMaxx
Wil,
Sweet Bodies dude... I don't even want to know what you charge...

Those are HOT though, Very nice work...

 

[HP Invent]

Re: Shimming a diff

Originally posted by SparkyMaxx
How do you shim a diff? I do not know from what I can tell. I have shimmed my Emaxx Tmaxx a couple of times each and had EXCELLENT Results. I have never had problems with any other diffs I have done. However I cannot shim this Swift to save my life.

What is the trick. It looks like I have now torn up those little rubber washers on the inside of the diff. Do I have to install all new gears and rubber washers to get the Diffs to quit eating themselfs and seazing?

:flaming:

I just want to go and make a few laps consectutively... Is it so much to ask?

Help!

SparkyMaxx: The diffs are pretty easy to shim. What you'll need are some 5mm shims. I posted some part numbers last week that should be able to help you when you get them at your local hobbyshop. When you open up the differential housings, the first thing you'll see are 4 small beval gears and one large beval gear. I usually shim all the gears ( 4 small beval gears and 2 large bevel gears ). What alot of swift users have been doing is to shim the large bevel gear. When you remove the large beval gear, you'll notice a small set-pin. Slide that set-pin out and place a shim or two ( depending on thickness ) over the orange o-ring. And then slid the set-pin above the shims. If the pin doesn't slip through easily, then remove one shim ( if your using two of them. ) Do this for all 3 the differentials. It sounds complicated but once you get the hang of it, it'll be pretty easy to do. Once you complete one differential, you'll want to check for mesh. Take the differential in your hands and twist the outdrives. If it feels too tight, then remove a shim or use a thinner shim. Also, if you were to pull the diff outdrives away from each other; and there's some play, then you want to shim the diff with a thicker shim. You want to make sure that there is no play ( or tolorance ) when you pull the diff. outdrives away from each other. I know this sounds like alot of work, but once you get your diffs shimmed, I think you'll be all dialed. Oh, BTW, you'll want to replace that 4mm orange o-ring also inside the diff casing since yours are totalled ( part # 61801 ).

 

[UHFire]

403forbidden - I found a bumpstart box essential for running this buggy. Playing with that pullstart (mainly breaking in the engine) demolished mine rather quickly. That is given the fact that it was first engine break in :smoke: From what I understand having researched the pullstart when I purchased my Swfit and saw it wearing quickly, a bumpstart box is essential for anybody who doesn't mind carrying one around. PRP actually makes one with a built in mini toolbox.

 

[Race Director]

SparkyMaxx dude, I made my own shims and ended up putting .015" (0.4mm) shims behind each small gear and .008" (0.2mm) shims under each big gear pin

What we do with the electric car diffs is secure both outdrives with an allen key and hold both together or alternatively put 2 allen keys in a bench vice and lower the outdrives over them, then try to turn the main gear, if it skips it needs more shims, if it doesn't then rotate the outdrives in opposite directions to check for mesh tightness, if it's too tight take out a shim on each small gear (my shims were 2 thou thick BTW)

As HP said, the 1st one takes a while but you'll probably find all 3 are the same

THEN put your grease back in (I'm currently trying ptfe grease - seems ok)

 

[xxxzayas]

For all of you rebuilding your diffs. I would recommend using a high quality silicone oil for the diffs. It does not break down with heat and stays consistent. A good place to strat is 1000wt in the rear, 5000 in the front and 7000 in the center. Hope this helps.

JZ

 

[BigRed]

Anything bad about the Swift that I should know about? Thanks for the info!

 

[HIREz]

Yep, It's a good car..
is that bad?

Read through the complete thread so you know what to tighten down, tips on set-up, and steps taken to do these things.
I don't know of ANY other car manufacturer that has taken the time, or patience, to offer a near real time help board that's this legible.

My2Pennies..

-Will-
www.WilzWerx.com

Originally posted by BigRed
Anything bad about the Swift that I should know about? Thanks for the info!

 

[HP Invent]

There's an instructional on how to shim diffs on www.powerracingrc.com. This is pretty much how to shim diffs for all r/c cars that run an oil filled diff. Just look under the swift icon and open up building tips.

 

[SparkyMaxx]

Nice display on Diffs HP. Did you guys just put that up?

Diffs are not difficult. What you say on that page is what I did. The gears must jut be too worn down or the seals went and are causing problems inside. I don't know but I will investigate and post what I find.

It is just getting tiresome that I have to keep tearing it apart. I love the buggy I just want it to make a few laps before I have to wrench it yet again.

Oh well Trug on. After all look at the signature.

 

[HP Invent]

Originally posted by SparkyMaxx
Nice display on Diffs HP. Did you guys just put that up?

Diffs are not difficult. What you say on that page is what I did. The gears must jut be too worn down or the seals went and are causing problems inside. I don't know but I will investigate and post what I find.

It is just getting tiresome that I have to keep tearing it apart. I love the buggy I just want it to make a few laps before I have to wrench it yet again.

Oh well Trug on. After all look at the signature.

No prob sparkey. Once you shim all your diffs, you should be able to bash without worrying about the diffs. My diffs have gone through some serious racing and bashing. I haven't worked on my diffs since the beginning of last month. I changed out the oil for the U.S. gas champs, but thats pretty much it. Check this out, currently I have a .27 motor in my buggy. The thing is a beast with gobs of torque. From the stand still position, I can almost get the front tires off the ground . Let's see how long the diffs last in my car. I'll give you guys a full report.

 

[SparkyMaxx]

Well they are all torn apart. The center was LOCKED up again. The Diff Looks like it has a slight V to it. All three times I have taken the center apart it is ceased and in the V formation. It has always had the screws sticking out and not quite flush with the top of the gear. Could I have gotten a defective center diff case? The Front and rear seem ok. I was twisting the rear and it seems to bind when I do only one side. If I do them both at the same time it is smootthhhh but binds when only one is twisted? Why would that be? Is that due to not shimming the bevel gears? How do you ensure you do not shim the bevel gears too tight? It is hard to tell with them because you cannot grab the shaft and move them in and out... Suggestions? Thoughts?

 

[niggle]

Hiya,

Just ordered a PRP Swift from a supplier here in the UK, unfortunately they are on back-order from Schumacher so I guess I will have to be patient :depress:

This will be our second nitro car. We had a lot of fun with a CEN Fun Factor and got hooked, despite the fragility of the CEN and the poor availability of spares. Hopefully we will fare better with the Swift - 1:8 buggies in general seem to be a lot sturdier and better engineered than 1:10 off-roaders.

Just a few observations regarding "known problems" with the Swift: -

1. Soft diff drive cups (outdrives)
There seems to be some diffculty in obtaining harder versions that will go the distance. Assuming that the "shiny" CVDs are not just down to some cheap plating and they are actually made from some kind of chrome-steel, could it be that the drive pins on the dogbones are just too hard? Would it be possible to press in some softer drive pins into the dogbones? Will drive cups and/or CVDs from another manufacturer fit the Swift?

2. Diff gear meshing.
I've never rebuilt a diff so I don't know what degree of meshing is appropriate. Checking the pinion/spur meshing with a strip of paper has always worked for me. Could someone quote an appropriate feeler-gauge measurement to make this exercise a little more scientific? Where can I obtain suitable shims in the UK? CEN provide a few spare shims in the box for diff adjustments, maybe PRP could do the same?

3. Diff oils.
I'm guessing that the shear properties of the silicon oil are used to implement some kind of viscous coupling inside the diff, thereby promoting limited-slip characteristics. Viscosities quoted for the diffs appear to be 3000, 7000, 1000 for the front, centre and rear diffs respectively. I can understand the centre having the highest weight as you would not require much slip here, but why does the rear diff allow more slip than the front? I would have thought that on full lock, the wheel speed differences side-to-side would be greater at the front than the rear and therefore the diff would need to be relatively looser at the front and tighter at the rear.

4. Pivot ball suspension.
Not impressed with this on the CEN. Lots of play or binding, pivot balls tend to pop out and you lose the driveshaft somewhere in the grass. Is this type of hub any better on 1:8 cars? I notice a few other manufacurers (Mugen, Ofna) have started to adopt this design.

5. Glow plugs.
What's the best plug for the SH .21 engine running 25% nitro fuel in a cool [UK, 10 - 20 C] climate?

6. TX upgrade.
The Swift RTR comes with a basic twin-stick (AM?) radio set in the UK. I intend to upgrade to a computerised FM system but don't know whether to go for a stick or steerwheel TX. I'm happy to continue with a stick TX but I'm wondering if my 6 year old son might find a steerwheel easier to use? Comments appreciated.

Sorry to drone on for so long, thanks for reading.

 

[wagnerov]

Sorry for the delay, we were out testing our new monster truck yesterday.

1 & 2: Schumacher's next shipment of cars _may_ include the hardened outdrives and all of the differentials should be properly shimmed. Last time I was in China, I showed them how to do it (again! argh). When we refer to properly shimming them, we're talking about the 6 bevel gears on the inside, not the ring and pinion gears. Please refer to this thread 1-3 pages back, and you'll see more info on this subject than you probably need. Also, all the new Shumacher shipments of cars are purple, instead of the "champagne" color found on the U.S. version.

3: Excellent question. We simply want to create an inherent "push" to the feel of the car by running a lighter diff fluid in the rear, due to the lack of traction created by dirt. Although I haven't tried anything heavier than 3000 in the rear, I always end up going back to 1000 simply to make the car easier to drive. Sounds like someone does some full-size car racing...

4: Getting pivot ball suspension right is a pain. Some people do, some people don't. But once you do, it allows a little bit more adjustment (track width) than c-hubs. On the other hand, it's a tad heavier, and requires more maintenance. The jury is still out on whether or not it is better.

5: Any medium temperature non-O.S. glow plug will work fine. Stay away from the hot plugs, they'll make it easy to start, but they'll burn out quickly.

6: I think Schumacher sells the Futaba radio with the Swift. Personally, I don't think pistol-grips are any better than stick radios. After driving a stick radio with our boat, I see an advantage with throttle control, and maybe that's why they are more popular over the ponds. But since I've been driving with a pistol-grip for 15 years...it's a little hard to change.

Hope that answers your questions. Thanks for buying a Swift! Say hi to Robin for me.

 

[Diver6127]

You guys are killing me with that new MT you're testing. Especially after IMing ya about it. I feel like a nervous virigin in a cathouse with all expenses taken care of. May is coming around, I contacted Vito at NYC Hobbies, thanks to Roger for the info. I'm holding off on making the SS purchase because I wanna compare it to the Savage.

May is coming, is it going to make the projected unveiling? !@#$%^&, I'm getting unpatient and it's not even Christmas yet!

 

[niggle]

Wagnerov,

Thanks for taking the time to reply.

After my orginal post I found the "Build Tips" article on your website and that pretty much explains everything regarding shimming the diffs.
Can I assume that the shims used for the planet/spider gears are the same internal diameter (5.0mm?) as those used to shim the sun gears?
Can I also assume that the Mugen-Seiki pack of 25 shims (C0227) that you mentioned in an earlier post contains an assortment of thicknesses?

I don't know what sort of relationship PRP have with Schumacher (and frankly it's none of my business) but anything that you can do to ensure that the UK has a good supply chain for Swift spares will be very welcome. The crappy weather in the UK makes the off-road season very short and the last thing we need is our cars sat on the shelf for weeks waiting for spares.

It's a shame that the UK versions don't have the MX3 radio set. I am resigned to ditching the basic twin-stick set that we get and buying a Hitec Aggressor CRX. The Sanwa/Airtronics MX3 would be more than adequate if we could get it at the right price in the UK.

Good luck with the Swift, it would seem to have a lot of potential and with your support I'm sure it will be a great success.

Is there any mileage in using graphite powder or dry film lubricant in the pivot ball hubs or is it just a case of keeping them clean?

Will bodyshells designed for any of the following fit OK on the Swift chassis?

GS Storm
Mugen MBX5
Kyosho MP 7.5

--

 

[UHFire]

I just got my new Diff gears today, and I have to replace all three in my buggy. I have never performed this procedure, however I own all the correct tools and have done minor fixes (CVJ fun). With the exploded diagram next to me, what kind of time commitment is this procedure? I only ask because I'm going to try to squeeze some car work in berfore a huge load of the lesser important -- school work. Thanks!

 

[wagnerov]

Most of the time, I don't shim the smaller bevel gears...but that's mostly out of laziness (knock on wood). But if you do, they use 4mm shims the shafts. You can probably get away without running 4mm shims. The Mugen pack will contain everything you need. We also have our own shim set, #61401...I'm not sure if Schumacher carries that or not, but seeing as they are racers like us, they probably do.

We just run the pivot balls as they come out of the box, dry. No oils, lubricants or anything like that, although we haven't tried graphite yet.

Mugen and Kyosho bodies, especially from Pro-Line, fit fine. The GS one is a little bit different, though.

Thanks for the comments,

-Cameron

If it's your first diff assembly, for all three, plan on at least 90 minutes if the diffs aren't out of the car already.

If they are, it won't take more than 10 minutes per diff, for those of us who have it down to a fine art! Less experience may be 15-20 minutes per diff. Patience reeeally pays off.

 

[niggle]

Cameron, thats great. Thanks for your support.

Now it's just a case of waiting for the container ship from China to come in...

 

[HIREz]

3xx) The diff oils in the 1/8th scale Q I think you're asking is more relevant to thinking of it in a "posi-traction" way, the higher the oil the more it is likely to not let the diff work through the turns, and hold both sides , left to right, power application, in turning, think the same way, if u take a posi'd car onto a twisty track, the higher the posi level the more apt that end of the car is likely to slide out, so when Waggs says he ran 3K in the rear but went back to 1K its because he wanted to free up the diff so the rear end followed the track smoothly and slide out when he went 3K,,,, not because it had viscous coupling capabilities. unlus you use a torsen diff, then you can get into the whole viscous thang...
speaking of which, will any of the torsens out there fit the swift?
(please chime in PRP doods if this sounds way off as I don't want to throw anyone off here)

4xx) The swift has a deeper pillow system than the cen cars, if you look at the pics you can tell right away the cen has about 3/8 of an inch from front to back of the ball, which doesn't house the ball securely giving the syndrome you're speaking of, popping out or when some person tries to correct this, and overdoes it, a binding from overtightening.
with such a deep pillow system such as the swift, or mugen / ofna for that case, the whole ball is encased in a very secure or thicker pillow "case", lols, so the pressure is contained very well and there is no flex in the housing to give that "popping out" shiznit.

am I crazy? seems to work so far?

p.s. PRP call the Pinole store and sell them on the swift, another dark force is starting to taint the mind of management.. hurry please...

-Will-
www.WilzWerx.com

Originally posted by niggle
Hiya,

3. Diff oils.
I'm guessing that the shear properties of the silicon oil are used to implement some kind of viscous coupling inside the diff, thereby promoting limited-slip characteristics. Viscosities quoted for the diffs appear to be 3000, 7000, 1000 for the front, centre and rear diffs respectively. I can understand the centre having the highest weight as you would not require much slip here, but why does the rear diff allow more slip than the front? I would have thought that on full lock, the wheel speed differences side-to-side would be greater at the front than the rear and therefore the diff would need to be relatively looser at the front and tighter at the rear.

4. Pivot ball suspension.
Not impressed with this on the CEN. Lots of play or binding, pivot balls tend to pop out and you lose the driveshaft somewhere in the grass. Is this type of hub any better on 1:8 cars? I notice a few other manufacurers (Mugen, Ofna) have started to adopt this design.