Thanks for the warm welcome guys, I have spoken to Roger who works at PRP, He has very kindly replied to my emails and briefed me on what to do during my rebuild, Going to pick it up tomorrow though, Can't wait to get my RB fitted and take it for a blast, I've not run my RB for a while now during the winter break, I love this engine to bits!.
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PRP Swift
- Thread starter Lightfytr
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Originally posted by Lightfytr
spidey have you upgraded your steering servo yet, if you have or not you may have some type of interference with your radio also, not sure just a thought.
I haven't ugraded the steering servo yet, but it's a planned upgrade. I don't think it's the servo though, the car seems fine at less than half throttle and when I let off the throttle. Half throttle or more is when it starts to pull. I'm new to 4wd, but is it possibly a problem with the differentials or something? It's barely been used, so I didn't want to already start taking everything apart. Now that I think about it, I don't see what else can be the problem. All my CVJ pins are in and I loc-tited all the set screws. I'm still waiting to take this thing off-road since I barely made it through the break in process because of lost pins and now this.
Spidey: hummmm, interesting. Are you driving on dirt or asphalt ? Here are a few things to check:
1) Radio: make sure that all your end points on your radio are balanced. Also check everything that's related to steering on your radio. I always have this issue with my touring car ( TC3 ) cause of the excessive amount of torque steer.
2) Mechnical: Toe-in/out on your front wheels. Make sure they are even on both sides.
3) Make sure that your servo saver is not set too tight.
These are things that I checked out with my touring car when I had that issue. Hope this helps.
nitro4mikey
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Right on the money guys....
Steering trim should be the fix.. If you are testing on the street, you will see MORE torque steer than on dirt.
I have been thru this with my other rc's. It wont be a diff problem cause you would hear some gear skipping/grinding. Also check the toe settings as stated prior.
Thats my opinion on this.
Steering trim should be the fix.. If you are testing on the street, you will see MORE torque steer than on dirt.
I have been thru this with my other rc's. It wont be a diff problem cause you would hear some gear skipping/grinding. Also check the toe settings as stated prior.
Thats my opinion on this.
Thanks for the input guys. I'm driving on pavement right now since I pretty much only got to do the break in so far. It just started happening out of the blue. I ran it at full throttle up and down the street after I got the engine tuned and I was really happy with it. Near the end of that tank of fuel it just started to happen out of the blue. I wonder if maybe it's just torque steer. After I broke the engine in and had it tuned pretty well, I noticed the front tires would spin really easily on the pavement. Only the front though, it didn't look like the back was breaking loose. Should the power be more equally transferred to all tires since it seems like the front is where the power is? It kind of makes sense if the front tires seem to be doing more of the work for there to be torque steer as a result. Are there any adjustments that can be made to maybe even out the power distribution betwen the front and back tires to be more even?
Anyways, I appreciate you guys reading my long drawn out posts. I'll take it out tomorrow on the dirt and see if the same problem occurs. Thanks again for all the suggestions so far.
Anyways, I appreciate you guys reading my long drawn out posts. I'll take it out tomorrow on the dirt and see if the same problem occurs. Thanks again for all the suggestions so far.
Hehe, yeah I'll check the brakes. I'm all bummed out about figuring out what's wrong with my buggy that I didn't even check the little things. Looks like I'm going to be spending a few good hours tomorrow thorougly going over the entire car to make sure everything's adjusted right. Thanks again.
Originally posted by HP Invent
Spidey: Shimming the diffs means you have to shim the internal gears. I only shim the 2 sun gears in each diff. The shims that you should be using are 5mm (inner diameter). I found a trick set of 5mm shims made from yokomo ( part # ZC-s50s ). Its a 5mm shim set that has various thinkness'. A must for any 1/8th scale buggy
Thanks for the part number. I just ordered those shims last night. I have a couple questions about the diff. What are the sun gears? Are they the large bevel gears? I'm looking at the diagram and each diff looks to have a steel gear, 2 large bevel gears, and 4 small bevel gears. I'm also wondering if the diffs have grease or oil in them? If not oil, I'd like to add some but don't know how high to fill it. . Sorry for all the questions, I just want to know what I'm doing when I take the diffs apart. I'm planning on opening them up now so I can install the shims as soon as I get them in a few days.
Kewl. you'l be happy with the shim kit. The sun gears are the 2 big gears. I used mugen diff oil in my swift. Diff weights are as follows: 3000 front/ 7000 center/ 1000 rear. You want to fill up your diffs up to the point where the two shafts that holds the bevel gears. Don't overfill your diffs.
nitro4mikey
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The small gears are called ""Spider"" gears
I think I figured out what the problem with my Swift is. It seems like it's basically just front wheel drive. Holding the car off the ground and giving it gas makes all four tires spin. When I put it in the grass it was obvious the front tires were doing all the work. On a thick patch, the front tires would just spin and spin while the rear tires did nothing. The pins for the center driveline are all in, so it's not that. Does this mean the rear transmission is shot? I was going to take it apart anyways to put some shims in, just thought I'd ask if anything besides the rear tranny could be the problem? Damn, I kind of wish I spent that $500 on a different car now. A whole month and I've barely drove it. 
Ok, I got my Swift today and have spent most of the day working on it, So far I've put my MBX-4 upper arms on, Rebuilt all the CVDs and Rebuilt the Front Diff. First impressions where quite good, But after spending time with the car it was obvious that it wasn't up to the same build standard as some of the other cars, I don't think its as good as my H7 was but better than the Crono, Also I was not remarkably impressed with the diffs, They looked tiny and not very durable, Also they where made from untreated steel and already showed signs of rust, My Crono diffs where the same. I also noticed quite a few of the screws have been stripped on the underside of the chassis, They certainly do like using loctite! Shame they can't use any on the drive pin securing grub screws for the wheel hubs, One was actually loose completely!, Also I don't like the brake disks, They are made VERY thin, Almost like tin foil and the pads where also not that much better, They two where very thin. Finally the only other thing I did not like where the shock caps, Mounting the solid aluminium shock cap on a aluminium ball stud is not that great of an idea!, I am sure I can sort a fix out for this though. Those are the bad sides, And they are, I have to say relatively minor, Things can be replaced aslong as they aren't too dear, Overall I would say the car is definetely worth the price tag and then some.
My LHS said Mugen diff oils are cps and not wt. Therefore 100000 of mugen silicone oil is equivalent to more or less 10,000 wt of AE, Losi or any american oil. 10,000 cps mugen is 1,000 wt.
Some USA based companies are still using the "WT" rating, where Japanese and European companies use the better linear Centi Poise rating. A lot off people think that the ratings between the "WT" and "Cps" ratings are linear but this isn't the case. For shock absorber use, this is the comparison table when using LOSI, ASSOCIATED and SERPENT silicone oil rated in "WT"
100 Cps 10 WT
150 Cps 15 WT
200 Cps 20 WT
275 Cps 25 WT
350 Cps 30 WT
425 Cps 35 WT
500 Cps 40 WT
The 50 Cps steps between "Cps" rating are linear, where the 5 WT steps used in the "WT" rating are progressive compared to the real thickness of the oil.
so if you put mugen 5k/7k/1k you actually just put 500/700/100 wts. on your diffs. Thats too light for your diffs.
Thx for information. I'm just going by the number that is labeled on the actual diff. oil despenser. WOW, 100000 diff oil from mugen is equavalent to 10000 AE or Losi diff oil ? 100000 diff oil is pretty thick. I have some for my MRX-3 and MTX-3 and that stuff barely comes out of the despenser because its so thick. Now, when you say 5K=500, 7K=700, and 1K=100, are you comparing diff oil to shock oil. From what I remember, isn't diff oil alot thicker than shock oil ? What diff oil combination are you using ? Again, thx asar
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Thx.swift diff oil
HP Invent, I suspect that PRP made a mistake in their manual putting 5,000 wt/7,000 wt. / 1,000 wt. front /center/rear differentials for the Swift. I think it should be cps. as what is used in kyosho and mugen silicone oils.
Can anyone from PRP please confirm....wagnerov.
I have all the mugen silicone oils and 10k. 30k, 50k, 70k and 100k and HP invent is right, 50k up is really thick.
I just got a new Kyosho Kanai 3 and the silicone oils included in the kit are only 4,000 center and 1,000 rear and this are in cps not wt. front oils is a red oil (no # or weight, supposed to be for LSD)
Attention PRP, please clarify.
HP Invent, I suspect that PRP made a mistake in their manual putting 5,000 wt/7,000 wt. / 1,000 wt. front /center/rear differentials for the Swift. I think it should be cps. as what is used in kyosho and mugen silicone oils.
Can anyone from PRP please confirm....wagnerov.
I have all the mugen silicone oils and 10k. 30k, 50k, 70k and 100k and HP invent is right, 50k up is really thick.
I just got a new Kyosho Kanai 3 and the silicone oils included in the kit are only 4,000 center and 1,000 rear and this are in cps not wt. front oils is a red oil (no # or weight, supposed to be for LSD)
Attention PRP, please clarify.
Roadrash13
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Mugan oils: their rating sys. is confusing to say the least!
Their 100,000 = 10,000
70,000 = 7,000
50,000 = 5,000
10,000 = 1,000
in most other brands (GS, Ofna ect..)
Why they do this who knows, as per all the other threads have mentioned. Hmmmm....
So if in fact you put the combo you listed in your post, you should be fine! :whhooo:
Steve
Their 100,000 = 10,000
70,000 = 7,000
50,000 = 5,000
10,000 = 1,000
in most other brands (GS, Ofna ect..)
Why they do this who knows, as per all the other threads have mentioned. Hmmmm....
So if in fact you put the combo you listed in your post, you should be fine! :whhooo:
Steve
*Bump*
Where has everyone gone? :\
Finished rebuilding my car today, All the diffs are shimmed and seem to be meshing pretty good, Just a little bit of play and they are running very smooth indeed.
Some other things I want to address people of, During building I have done a few extra things based on my experience. During shimming the diffs I found the front/rear pinion gears to have a little too much play, So I put another thin shim behind the existing two that are already there, This tightened the pinion up a little bit more against the ring gear also, Which is also IMO better now, But best of all has to be the fact that there is only now a tiny ammount of slop left, Having as little or no slop at all is crucial to having accurate running diffs. I also replaced the shock mounting balls with a piece of fuel tubing, I mentioned in my first post that I was not overly keen on the standard method, And while searching TWF8 I found a trick as used on the MBX4 (MBX4 used the same shock mounting design), You can find the details here (Scroll down to Tip 18
Overall I am quite impressed with the car, I'm just a little nervous still on how these diffs are going to hold up, I'm not also keen on waiting to see how much the drive cups wear as they will be a absolute nightmare to replace.
Where has everyone gone? :\
Finished rebuilding my car today, All the diffs are shimmed and seem to be meshing pretty good, Just a little bit of play and they are running very smooth indeed.
Some other things I want to address people of, During building I have done a few extra things based on my experience. During shimming the diffs I found the front/rear pinion gears to have a little too much play, So I put another thin shim behind the existing two that are already there, This tightened the pinion up a little bit more against the ring gear also, Which is also IMO better now, But best of all has to be the fact that there is only now a tiny ammount of slop left, Having as little or no slop at all is crucial to having accurate running diffs. I also replaced the shock mounting balls with a piece of fuel tubing, I mentioned in my first post that I was not overly keen on the standard method, And while searching TWF8 I found a trick as used on the MBX4 (MBX4 used the same shock mounting design), You can find the details here (Scroll down to Tip 18
Overall I am quite impressed with the car, I'm just a little nervous still on how these diffs are going to hold up, I'm not also keen on waiting to see how much the drive cups wear as they will be a absolute nightmare to replace.