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New Case Halfs

11464 Views 58 Replies 21 Participants Last post by  blasterman88
Hey guys, I brought the topic of manufacturing new case halfs awhile back since we all know that at some point the supply of oem honda ones will be gone. Well I've gotten the equipment i needed to copy the oem ones, so here is where i am at.

I am in the process of talking to casting companies to try and determine the cost, and the amount of cases that would be required. I am still trying to determine the feasability as well as the demand for them. So if i was able to reproduce them would people be interested?? I would also get with C-Leigh Racing to discuss the possibilites of strengthening known weak points, would you guys be interested in these?? I'm just trying to gauge interest before i invest too much money and time.

So if this project does continue i will need a couple of people to volunteer case halfs that i can 3-D image. What i need are a left half and a right half. I know that some of you guys have undamaged ones laying around. I realize that you will be shipping them to me based on faith, and if there are any concerns or if you are interested please PM me. All I am trying to do is make sure that these machines live on.

So if you guys have any input please feel free to email me [email protected], PM, or post here. Any help or comments will be appreciated.

I am also working on getting examples of what the 3-D scanner can do. When i get these examples i'll be sure to post them.

Thank you for your time.
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Thats a good idea & leave out those cavitys between the studs, make them solid.
wow I'm getting alot more responses over here.

I was already planning on allowing the extra room, since you can still run a stock cylinder on cases that have been machined, and that way it would save people time and money.

And i'm planning on doing alot of reverse engineering. I'm also very profficient in 3-d programs (i.e. solidworks, CAD, etc) i'm a 4th year mechanical engineering student. Rich over on one of the other forums also brought up the idea of modifying the right case and clutch cover to allow the use of a 88-91 CR topend and power valve, which i think has potential i just have to see if its feasible with the room allowed.

Beobe already brought up the idea of oversees casting which i think would be a better alternative due to cost. This would allow me to get the price down. I need to get a general design that way i can send out the model for price quotes. I need to figure out what kind of volume minimum casting companies have. I don't have an unlimited amount of cash up front.

For all of you guys that volunteered cases i really appreciate it. I need a right and a left, so if you are interested in volunteering them, please PM. I'll get you my address and contact information. I will probably need the cases for about a week, maybe two. So if you have time constraints on there use please let me know.

Once again thanks for all of your input.
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Were there any notable differences between the 86-87 case halves, and the 88-89? And i was wondering what kind of price you guys would be looking to spend on cases either as a set or individual pieces?

And would anyone be interested in run of quick change clutch covers?

Thanks for all of your input guys.
Thats good, i was hoping that there weren't any major differences. And if you can find that right case half I'd appreciate it. Like i said it should only take a couple of weeks to model, and I will reimburse you for the shipping cost.

An example of the 3-D modeling that can be done can be found here:
make sure you have adobe 7.0 or higher. I will be able to do this with the case halfs as well.
if your gonna do "quick change" covers ..(clutch covers)... there is also 2 different covers that work for these R motors
thanks for the correction. Is there one style that is preferrable to the other? And if so could you give a link? Thanks,
Great idea on the cases. I think there will be plenty of interest. The idea on taking the voids out is a great idea. This will leave a ton of big bore options although the new CP industries cylinders (Saber and I'm assuming the Puma, get on the Planet Sand website and get Calvin's number to check for sure) use the voids. This portion is partially machined out so the sleeve can plug into it. It makes for a very strong and long sleeve which is a great feature. I personally would make them as stock to start, alot of people like keeping the crankcase area small to keep velocity in the transfers up. All the big bore cases that have had a 250 cylinder on them I have ridden seem to be a bit soft on the low end and this is a factor. Let the builders machine for the big bore.

One thing I would like to see for the bigger motors is the ability to adapt a CR250/500 clutch basket on to the TRX. I have a CR 500 and haven't seen if the splines are the same for the shaft that the inner hub gear goes on, and I know there would be some messing around with primary drive gears but these baskets are larger and the inner hub runs 6 clutch springs instead of 5 like the TRX. When you build a higher HP/Torque big bore and you want to use the clutch (don't use override tranny and lockup clutch) it's hard to keep clutches in them. An 8 plate clutch setup for the TRX is a fix but the springs you have to use and stiff as &*^%.

Gear sets need to be the next thing looked at. Honda won't make these anymore either one of these days. Yukon only makes one side.
I agree on the voids, those will be filled in solid as suggested. Although the exotic big bore kits use them i don't think that the demand will be great enough to outweigh the stock or mild big borre uses. I'm still up in the air on the pre-machining for the big bores. I haven't ridden a stock bore that has been machined for a big bore. One possibilty is to have them all cast stock and then machine a few of them to have on hand. That might be the best alternative to keep everyone happy.

I am contemplating the idea of actually CNC the cases out of billet for the sand drag guys, upon request of course. Although the price tag for them could be extremely high, most likely around a grand or more.

I'm not sure about the CR 500 clutch basket. I didn't really plan on reengineering the drive. That would be extremely expensive and although it would be nice, i don't think i have the resources.

I also agree on the gears, and that could definitely be a possibility as it could be rather simple to have gears cut once i know the specifics of the gears.

Once again thanks for the input. Its all very helpful.
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found the right side.
just need left anyone?
Awesome...Thank you. Email me at [email protected] for my address and any other information you would like.
Left side anyone?
i sent you the right side you should have it in 7-11 days

I appreciate it man. If you let me know the cost and give me an adress i can send you a check to reimburse you for the shipping cost. I really appreciate your help in this endeavour.

Are there any left case halves out there???
my spare left case is hammered dog $h!t on the inside from blowing up 3rd early in a race. outside chain guide tabs are perfect though...
haha i appreciate the thought man, but i need one that is still in working condition. Since the new ones will be mostyl modeled after the old ones. I know that the left case is going to be harder to find due to the fact that its the one that usually gets busted. haha.

I reall just don't want to have to tear apart my bottom end to get a clean case. Although i guess i could spruce up the bottom end. But if someone has a clean one i could get this project going much quicker.
don't worry about it it was only a few bucks.
just let me get first crack at buying these cases when they get made :)
and if you decide to make the quick change covers also :)
I think i could cut some kind of discount for the people who help... ;)
I've got a few, busted though, you could still get measurements off of them anyway. Can you use one like that.
Sorry, I hadnt gone to page two.
If the cases are still in pretty good shape aside from cracks then I could probably use them. The way that the 3-d scanner works is that you move this camera around the object and it takes multiple pictures. The computer will then post-process the pictures and combine them into a 3-D image. When all is said and done the scanner will give precision to somewhere around 0.00006".

So if the cases are nice and stright then I am pretty much done as soon as they are scanned, because the tolerances don't need to be that tight as most casters cannot reach those tolerances. With that being said if the cases are still in pretty good shape i can go in and "fix" the broken places with "patches" and that could work as well.

If you want to pick the nicest one you can send it and I'll take a look and see what i can do. As mentioned above in other posts I'll pay for all shipping.

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I've got one left case half that was busted from a thrown chain & then I took JB Weld & beefed up that area filling in the broken part.
Would that work or does it need to be all aluminum case.

I'll go through them & pick out the best & get them on the way, pm me your address.
The one with the JB weld would beperfect actually. It doesn't have to be all aluminum, it just has to be a continuous surface. I'll PM you my address.
Thanks Neil,
don't worry about it it was only a few bucks.
just let me get first crack at buying these cases when they get made :)
and if you decide to make the quick change covers also :)
Hey man i just wanted to let you know that i got the case half a couple of days ago. It'll probably take me a couple of weeks to gte it modeled etc. I just wanted to give you an update. I appreciate your help,
damn all this time & nothing from him .. hmmm :unsure:
Sorry man, I just graduated and bought a house. Its amazing how much time both of those suck from your life. There has been progress, and I've got some pictures of the work in progress that I need to post. Thanks for your patience.
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