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Discussion Starter #1
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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i think this is a great idea. i have a right side case half that i am pretty sure is still in great condition. i will have to dig it out of the shied and check. but if you need it let me know.
 

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I also think this is a great idea! I have a damaged left side case that you can have, it will still be good enough to get some 3-D images and modeling of it I believe. If you need it, feel free to PM me.
 

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Nick,
I'll be glad to help any way I can.
Just some things you might need to think about & maybe already have.
Cost of the casting itself if done in the US as opposed to overseas market. Might could contact Airsal, in Spain for the casting process & then you do the machining.
Far as strenght issues of the stock case design, make them thicker around the outside under the crankshaft area & maybe beef the area around the shift shaft on the left case.
Every time you see a busted left case half its from a thrown drive chain & that wouldnt happen if Honda had designed a chain guide on the stock swingarm like the aftermarket arms have.
Neil
 

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I would also check out block castings..(skip the initial casts $'s) & fees related to
the outward appearance dont have to look exactly same ..its the inside & mounting that matters ;)


a very good programmer , 3-d (& 3-d models etc) & reverse engineering could save tons on some stuff..
never underestimate the modern 120-150 tooled "revolver type" mills nowadays ..its run time costs that could kill it ..if ya if ya have to pay for "specials" runs at an expensive shop
 

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just an idea. what if the cases were cast so that you can run a big bore cylinder with out having to send the case back out to get remachined to except them. then you can run a big bore or stock cylinder. just an idea
 

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just an idea. what if the cases were cast so that you can run a big bore cylinder with out having to send the case back out to get remachined to except them. then you can run a big bore or stock cylinder. just an idea
Thats a good idea & leave out those cavitys between the studs, make them solid.
Neil
 

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Discussion Starter #8
Thats a good idea & leave out those cavitys between the studs, make them solid.
Neil
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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Discussion Starter #9
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.
 

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the only real difference is that the cases got thinner as the years progressed ie 86 thicker than 89
quick change clutch cover great idea
i am still looking for my right side case half i seem to have misplaced it if you still need one i can go looking again.
however i did find all those missing parts i had to rebuy.
 

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Discussion Starter #11
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:
http://members.dslextreme.com/users/fireburns/carexample.pdf
make sure you have adobe 7.0 or higher. I will be able to do this with the case halfs as well.
 

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if your gonna do "quick change" covers ..(clutch covers)... there is also 2 different covers that work for these R motors
 

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Discussion Starter #13
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,
Nick
 

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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.
 

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found the right side.
just need left anyone?
 

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Discussion Starter #16
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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i sent you the right side you should have it in 7-11 days
 

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Discussion Starter #20
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???
 
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