Scott Morahan Posted October 22, 2016 Share Posted October 22, 2016 Hi everyone this is my first time posting on here but I do need some help, ive got a hpi bullet St 3.0 nitro, and I've got issues with the front left and right dogbones, I have got stock ones on the front as well as the hub carriers, but for some reason it seems as thought my dogbones no longer fit correctly it's like they are now to short, so I changed the hub carriers to aluminium ones thinking that might help but it was just the same, if I pull the axle to fit the wheel back on the dogbone will be right on the edge of the joint that I'd coming out of the diff casing and if I got to start driving my car the dog bone will just fall out of the joint. The stock dogbones are 87mm end to end, so I have ordered a set of 4 dogbones that measure 3.5" which is 88.9mm, I'm hoping that with the little bit of extra length they might fit ok. It has stumped me as even when all the stock items was fitted onto the car they still wasn't long enough. If anybody has came across this kind of problem before any help would and info would be much appreciated, also I was thinking of ordering some cvd driveshafts as I'm led to belive that these are a bit longer than the stock dogbone and axle when they are connected together. Anyway if any photos are required plz let me know in any messages and I'll get some taken, thanks scott. 1 Quote Link to comment Share on other sites More sharing options...
Vr5fx Posted October 22, 2016 Share Posted October 22, 2016 4 minutes ago, Scott Morahan said: Hi everyone this is my first time posting on here but I do need some help, ive got a hpi bullet St 3.0 nitro, and I've got issues with the front left and right dogbones, I have got stock ones on the front as well as the hub carriers, but for some reason it seems as thought my dogbones no longer fit correctly it's like they are now to short, so I changed the hub carriers to aluminium ones thinking that might help but it was just the same, if I pull the axle to fit the wheel back on the dogbone will be right on the edge of the joint that I'd coming out of the diff casing and if I got to start driving my car the dog bone will just fall out of the joint. The stock dogbones are 87mm end to end, so I have ordered a set of 4 dogbones that measure 3.5" which is 88.9mm, I'm hoping that with the little bit of extra length they might fit ok. It has stumped me as even when all the stock items was fitted onto the car they still wasn't long enough. If anybody has came across this kind of problem before any help would and info would be much appreciated, also I was thinking of ordering some cvd driveshafts as I'm led to belive that these are a bit longer than the stock dogbone and axle when they are connected together. Anyway if any photos are required plz let me know in any messages and I'll get some taken, thanks scott. Hey bud. I also have a Nitro bullet, and my dog bones are constantly falling out, I might buy CV/UV joints instead when I run out of normal shafts. If I remember correctly, there are also 2 lengths of dogbones, 86mm for the rears, and 87 for the fronts, or 87 for both, mine came with 2 different lengths. Also check that the cushions are still in the drive cups, stock they are black O-rings, which help keep the shafts snug, If these have come out, put some fuel tubing (around 2-3mm) in each cup. this holds the shafts in place, until you have a tumble and then you lose them again. Let us know how the longer shafts go as well Quote Link to comment Share on other sites More sharing options...
Scott Morahan Posted October 23, 2016 Author Share Posted October 23, 2016 Thanks for the quick reply, these drive cups your on about, they are where the dogbones sit in, which in turn, turns the wheel but do they also go into the cups coming out of the cups that in the diff casing? If so I don't think any of my have any in, also these o-rings your mentioning, do they look like a miniature round float that goes round a childs waist when they go swimming? I think I've seen them in black and orange. As soon as I recieve the longer dogbones I will let you know how they go, hopefully they will do the job and they never fall out again. The cvd driveshafts are supposed to be longer, but I ordered some of ebay and they ended up being shorter than the stock dogbone and axle put together, so got a full refund on them and they let me keep them (2 sets of 2), the back ones fit ok it s just the front ones I'm having a nightmare with. Yh so hopefully longer shafts no more issues, I'll keep you informed pal. Quote Link to comment Share on other sites More sharing options...
Fly In My Soup Posted October 23, 2016 Share Posted October 23, 2016 1 hour ago, Scott Morahan said: Thanks for the quick reply, these drive cups your on about, they are where the dogbones sit in, which in turn, turns the wheel but do they also go into the cups coming out of the cups that in the diff casing? If so I don't think any of my have any in, also these o-rings your mentioning, do they look like a miniature round float that goes round a childs waist when they go swimming? I think I've seen them in black and orange. As soon as I recieve the longer dogbones I will let you know how they go, hopefully they will do the job and they never fall out again. The cvd driveshafts are supposed to be longer, but I ordered some of ebay and they ended up being shorter than the stock dogbone and axle put together, so got a full refund on them and they let me keep them (2 sets of 2), the back ones fit ok it s just the front ones I'm having a nightmare with. Yh so hopefully longer shafts no more issues, I'll keep you informed pal. I agree with vr5fx, sounds like you've lost some drive cup shims ( on the diff side) If your new, longer, shafts still have too much play, simply shim the cups from the rear to minimally extend the drive cups outwards Shimmy shimmy Coco pops Quote Link to comment Share on other sites More sharing options...
Scott Morahan Posted October 23, 2016 Author Share Posted October 23, 2016 Thanks for the quick reply, these drive cups your on about, they are where the dogbones sit in, which in turn, turns the wheel but do they also go into the cups coming out of the cups that in the diff casing? If so I don't think any of my have any in, also these o-rings your mentioning, do they look like a miniature round float that goes round a childs waist when they go swimming? I think I've seen them in black and orange. As soon as I recieve the longer dogbones I will let you know how they go, hopefully they will do the job and they never fall out again. The cvd driveshafts are supposed to be longer, but I ordered some of ebay and they ended up being shorter than the stock dogbone and axle put together, so got a full refund on them and they let me keep them (2 sets of 2), the back ones fit ok it s just the front ones I'm having a nightmare with. Yh so hopefully longer shafts no more issues, I'll keep you informed pal. Quote Link to comment Share on other sites More sharing options...
Scott Morahan Posted October 23, 2016 Author Share Posted October 23, 2016 Hi fly in my soup, I'm new to these rc cars, im having to ebay the drive cut shims as don't know what they are, but would I have to take the diff casing apart to put thee ones in? 1 Quote Link to comment Share on other sites More sharing options...
Scott Morahan Posted October 23, 2016 Author Share Posted October 23, 2016 Could you possibly send me some pics of the part in question or even the product code number, thanks Quote Link to comment Share on other sites More sharing options...
Fly In My Soup Posted October 23, 2016 Share Posted October 23, 2016 2 hours ago, Scott Morahan said: Hi fly in my soup, I'm new to these rc cars, im having to ebay the drive cut shims as don't know what they are, but would I have to take the diff casing apart to put thee ones in? Sometimes yes, however, I have never disassembled a bullet diff, or shimmed one. It depends if the drive cups extend into the diff casing itself, sometimes they do, sometimes the drive cups are held onto the shaft via a grub screw accessible from outside the diff case, sometimes they are pinned from the inside. https://www.amainhobbies.com/kyosho-8x10mm-shim-set-10-kyo96644/p4067 Here are some generic d.cup shims from kyosho, a brand renowned for sloppy diffs Quote Link to comment Share on other sites More sharing options...
Fly In My Soup Posted October 23, 2016 Share Posted October 23, 2016 Also, get the old shims, if it indeed had any inplace in the first place to match up. Here is a full list of sundries for your St model, it's probs cheaper to buy from as hobby store, in regards to sundries http://www.wheelspinmodels.co.uk/c/271/ Quote Link to comment Share on other sites More sharing options...
Fly In My Soup Posted October 23, 2016 Share Posted October 23, 2016 I will have a proper look later, as I'm out with the three kids at the moment. Half term, ohhhh joy Quote Link to comment Share on other sites More sharing options...
Fly In My Soup Posted October 23, 2016 Share Posted October 23, 2016 Having another quick Google search. People with a similar issue on these bullet models, have rectified the issue with rubber o rings, like the ones you described, make sure you try and get a fairly soft compound silicone o ring so they don't bind up... Also, some geeza used springs inside the d.cups, but this sounds like a right faff, so I'm sceptical of this. Changing to cvd seems to be the most popular choice, although some say they are too weak, so went back to original dogbones with o rings in place If your strapped for coin, then you could try silicone fuel tubing, as vr5fx mentioned, although this is hit and miss imo Hope any of the crap I just waffled helped Quote Link to comment Share on other sites More sharing options...
Kpowell911 Posted October 23, 2016 Share Posted October 23, 2016 Common problem. Cut some fuel tubing and stuff it in either side of the outdrives Quote Link to comment Share on other sites More sharing options...
Scott Morahan Posted October 23, 2016 Author Share Posted October 23, 2016 Ok just ordered these from ebay to attach onto the cups and then tighten them up with the grub screws, what do you think, cos I think it will extend the original ones abit. Quote Link to comment Share on other sites More sharing options...
Fly In My Soup Posted October 23, 2016 Share Posted October 23, 2016 1 hour ago, Scott Morahan said: Ok just ordered these from ebay to attach onto the cups and then tighten them up with the grub screws, what do you think, cos I think it will extend the original ones abit. Firstly, These are drive cups, they look like driveshaft cups, not dogbone drive cups Not sure what you mean by attach these to the cups.?? You could attach these to the shafts protruding from the diff case, PROVIDED that there are shafts protruding with separate cups attached like these, not the more common 'one peice' drive cups, that are basically a drive cup that protrudes from inside the diff case itself ( shaft and drive cup are milled from same piece of alloy) Quote Link to comment Share on other sites More sharing options...
Vr5fx Posted October 23, 2016 Share Posted October 23, 2016 3 minutes ago, Scott Morahan said: Ok just ordered these from ebay to attach onto the cups and then tighten them up with the grub screws, what do you think, cos I think it will extend the original ones abit. These wont work, nor will they fit. On the bullet the diff cups extend and go inside the diff casing, and directly attach to the gearing inside. I kept popping a shaft out today, even after massive amount of fuel tubing and insane camber it still kept coming out. Quote Link to comment Share on other sites More sharing options...
Scott Morahan Posted October 23, 2016 Author Share Posted October 23, 2016 This is what it says about this item. Quote Link to comment Share on other sites More sharing options...
Kpowell911 Posted October 23, 2016 Share Posted October 23, 2016 They don't look like they'll fit tbh Quote Link to comment Share on other sites More sharing options...
Burridge Posted October 23, 2016 Share Posted October 23, 2016 This is what it says about this item. As said, if the cups are one piece with the shafts then they won't fit. Easiest way to check is to see if there's grub screws on your existing drive cups. Quote Link to comment Share on other sites More sharing options...
Scott Morahan Posted October 23, 2016 Author Share Posted October 23, 2016 Well I can try them when they get delivered as have to wait for the longer dogbones to turn up yet anyway so we'll see but I'll keep informed on here. Quote Link to comment Share on other sites More sharing options...
Fly In My Soup Posted October 23, 2016 Share Posted October 23, 2016 (edited) B.S.P are hit and miss, in my opinion I get tired of their generic ' universal' listings. Looks like it's longer shafts for you N.b thanks to whichever staff edited this post Edited October 23, 2016 by Fly In My Soup Turning my unvalidated slander into an experience based opinion, :) Quote Link to comment Share on other sites More sharing options...
Scott Morahan Posted October 23, 2016 Author Share Posted October 23, 2016 Hopefully the longer driveshafts will do the job, I hate not being able to take my bullet out and do some bashing with it. Quote Link to comment Share on other sites More sharing options...
Vr5fx Posted October 30, 2016 Share Posted October 30, 2016 Any updates? Quote Link to comment Share on other sites More sharing options...
Scott Morahan Posted October 31, 2016 Author Share Posted October 31, 2016 No nine as yet still waiting for the dogbones to get delivered, I did order some of the o-rings as the diff cups didn't have any or the rear cups didn't either, but yh I'm going to need the longer ones, I messaged hpi as well explains the issue I was having and they said the longer dogbones should be fine as long as I've got a bit of movement left and right, it should be all good. As soon as the new ones come through I will update and post on here and let you know. Quote Link to comment Share on other sites More sharing options...
Scott Morahan Posted November 2, 2016 Author Share Posted November 2, 2016 (edited) Hi well I did receive the dogbones today but they are the same size as the stock ones, well , they are 3.5" which is 89.9mm so i know they are not going to fit, so yet again I've just had to order a different set from another buyer which are 97mm so hopefully they should fit, they will be here in about a week so will update more then. Sorry for the wait people but soon it will be sorted, then I can start bashing my car again, good times. Edited November 2, 2016 by Rover Man Censored swearing removed................RM Quote Link to comment Share on other sites More sharing options...
Fly In My Soup Posted November 2, 2016 Share Posted November 2, 2016 7.1mm difference?? Did you measure to make sure you Have that much play??? Quote Link to comment Share on other sites More sharing options...
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