I sent my clutch basket off for some meatier spring cups. Here's what they look like at nearly 12,000 miles on the odometer: They don't look too bad, IMO. They're still getting replaced. Next on the chopping block is my cam chain & sliders. Also going to grease the steering bearings, change the fork oil, and reinforce the subframe. Here's a big wolf spider I found in my back yard:
There was some slop in the basket, allowing the clutch gear to rub against the gear to the upper right behind it (can't remember what it's called). No damage worth worrying about, but I have installed a new clutch bushing.
This kind of work is pretty much as far into a motorcycle as I have ever been. I learn by doing, and buy the tools needed in the process. The more I tear into it, the less intimidated I become.
Are they the spring cups from Indy?, just curious because ive got some on their way from him and ive been wondering what they will last like.
Not going to try and do the rivets by yourself? I figured a press would be needed but I saw someone just heat them with a torch and then smack them with a ball peen hammer to flare them.
I have some spare rivets so i will try the hammer and or hammer/punch method first, if that does'nt work too well i will be using a press. I cant help but think it might be a bit difficult to get them nice and tight without using the press though. A think a better way to go about it would be to tap a thread in the drive gear and drill out the basket 1-1 1/2mm or so and try find some countersunk high tensile allen bolts to screw into the drive gear instead of having the rivets, wouldnt be easy to tap a thread in the drive gear though. After all thats how most clutches are fastened to the drive gear on bikes, seems like a long term solution to making replacing the spring cups a quick easy job down the track. Anybody tried this?
It sure would be nice not to need to mess with rivets, but I think there would be a clearance problem with bolts and nuts and the gear is probably too hard to machine.
There is no problem with clearance when using allen head countersunk screws and they do not require nuts which is why i would be taping a thread into the drive gear. These are the screws i would be using http://www.ebay.com.au/itm/COUNTERS...?pt=AU_Building_Materials&hash=item27c769cdc6, note how they would sit flush with the inside of the clutch basket just as the rivets do. I might just go and see an engineering/machine shop to see if they think they can tap the drive gear. If so i will be using these screws and forgeting about the rivets for good.
I work on aircraft and we use large stainless steel rivets all the time. To install them we use air hammers and you can pick VIP a cheap set from harbor freight tools that will last forever if you do not use them every day. I have all different brands at work and I would buy the harbor freight for personal use.
I've never heard of them coming loose on any clutch with the countersunk screws, obviously i would loctite the threads of the bolts when i put them in.
Yep, and Indy is doing the installation for me. $50 labor & shipping. I'm not confident enough in my ability to do the riveting myself. I called around locally and was having a rough time finding someone to do it. Once you put Indy's spring cups in place, I doubt you'll be doing the job again. His are pretty tough. Here's what they look like:
Alright so i got my spring cups from indy and installed them...heaps chunkier than the originals so they should last quite a while. As i previously mentioned i did end up using allen head screws but unlike i thought i would have too. Instead once i had dissassembled the clutch backet/drive gear i realised i could drill out the holes in the rear retaining plate on the back of the drive gear where the rivets originally went through to 8mm and tap some threads in the clutch backet where the rivets went through and install some high tensile 5/16inch button/allen head screws from the drive gear side into the basket. I made sure i used some high strength loctite and got the screws nice and tight and i cant see them ever coming loose not to mention it must be alot more solid than just using the rivets. Sorry i didnt get any pics as i was in a hurry to get the thing together and ridable but im sure y'all can imagine what ive done and are all to keen to give me your opinions on my custom fix.
I hope it holds up for you. Just out of curiosity, how many threads do you think you were able to get in the basket?
I think about 6-7 threads into the basket. If i did it again i would use 8x1.25mm screws instead of the 5/16 screws i used simply because the threads are closer together on the metric screws therefore allowing more threads in the basket.
When threading weak materials like aluminum, especially when vibration is involved, it is good to get a minimum thread depth of one and one half bolt diameters. The basket is thicker than I remember then if you got that many threads. Good for you.
Dirtbike how is your project coming? I ask because I'm just taking my clutch apart and have just ordered new spring cups. I think your idea of threading the basket is a good one and plan on doing the same thing once I have a look at it all apart. I'm in the process of making a tool to hold the basket so I can easily remove the nut. My center bushing is also worn and needs replacing.
