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Discussion Starter #43
I'm hoping for the best but it looks lake a case of fraudulent advertising and I don't think I'd have the faith in DCR that you do.

"SKU: HON-CBR-500-S1
Great gains in torque and horsepower for the new CBR are easy with a set of DCR cams. With a "Drop in" design in mind we can grind a higher valve lift and duration for the stock valve train that picks up the torque and response from idle to top rpm. Power is boosted up to 8 hp and delivery is extra strong but smooth and predictable. Standard pistons, valves, and springs are recommended for best result with DCR cams" NOT A CHANCE!

I admire your spirit and willingness to provide a test bed for the cams. Seems to me you should be on the payroll for the feasibility testing and potential beta testing.

Paul
I am working with him to get the cams done and make it so that they will be drop in for the next customer. He stated that he has a customer in Pennsylvania that has been running them just fine on their bike.
I'm chalking it up to being a bad set. I sent the head and the stock cams to make sure that he can get all the information he needs to make them and he has been providing excellent customer service. So, yes, I'm confident that it will all be taken care of.
I wouldn't mind being on the payroll for beta testing either! :)
 

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I am working with him to get the cams done and make it so that they will be drop in for the next customer. He stated that he has a customer in Pennsylvania that has been running them just fine on their bike.
I'm chalking it up to being a bad set. I sent the head and the stock cams to make sure that he can get all the information he needs to make them and he has been providing excellent customer service. So, yes, I'm confident that it will all be taken care of.
I wouldn't mind being on the payroll for beta testing either! :)
Hope you don't get hosed on this deal. If he's got a customer in PA already running these he shouldn't need your head & cams to glean information from them: The PA guy should be proof he already had that info.

And if there was a CBR/CB500 guy out there running these cams he/she would have found this site -- or at least some forum out there -- and posted something about it. A simple google search of "CBR500R cams" doesn't seem to show a lot of chatter outside this forum out there.

Good luck.
 

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Discussion Starter #47
Hope you don't get hosed on this deal. If he's got a customer in PA already running these he shouldn't need your head & cams to glean information from them: The PA guy should be proof he already had that info.

And if there was a CBR/CB500 guy out there running these cams he/she would have found this site -- or at least some forum out there -- and posted something about it. A simple google search of "CBR500R cams" doesn't seem to show a lot of chatter outside this forum out there.

Good luck.

Thanks. I tend to give people the benefit of the doubt until they prove me wrong. I have to.....or I would go through life hating everyone, because people suck! Lol!

Yeah, I hadn't seen much chatter either. You can get stock cams and have them reprofiled as @tothezenith is doing. He might have gone that route when he created them. At least this way, he will have everything he needs to get it done correctly. He has been very helpful so far and I had heard the Crower name before this. I think it was his dad that did engine building, etc. Figured that hopefully the apple didn't fall far from the tree. So, I'm giving it a shot.
I will keep updating when I have anything new.
 

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I'm still trying to figure out how they are achieving a "higher valve lift and duration for the stock valve train" by grinding... ;)
 

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I'm still trying to figure out how they are achieving a "higher valve lift and duration for the stock valve train" by grinding... ;)
Technically, you can grind away base circle and get higher lift. If you grind away enough base circle you can also re-profile the lobe to alter duration a bit.

The thing with grinding base circle is that you need to make up the loss of base circle much thicker shims. You can end up with a situation like that shown in one of Joram's earlier pics:

 

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I agree with hondafan's post, if you build the lobes up first and then grind them down a bit they'd give more lift, although then I'd say we're talking about building up the lobes or extending them; the grinding would just be a minor part of the job.
I still don't get why the grinding away of the base circle would give a higher lift.
 

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Valve lift is lobe high minus radius of ground circle, reduce the ground circle with grinding and let the lobes untouched you get a higher valve lift. But you need also thicker shims then, because they need to fill the gap between closed valve and the cam with the reduced ground circle.
Blackfin hit the nail on the head in his last post.

Just to grind the ground circle is much easier and cheaper than to weld the lobes up and then grind them.
 

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Here's a simple drawing I just did that might help explain how the cam grinding works to increase lift by removing material:

By grinding the heel you counteract that removal of material with taller shims in order for the valve to still sit right in the closed position. When it opens, that extra distance added by the taller shim give you that extra lift.
For duration, you grind the nose flatter resulting in longer duration. However this would decrease lift; you can't just shim it up though, as in the closed position the valve would still be slightly open with the higher shim. So to add duration you have to grind both the heel and nose and increase shim height to retain the same lift.
 

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Discussion Starter #54
Just a quick update. I have the cams back (Got them yesterday) and will be installing and getting the bike running ASAP....It has been WAAAAY too long since I've been in the saddle! He did go with bigger shims, but I think he has it so that a 3.5mm shim will work. I will know more when I install....hopefully tonight.
I still have more wiring, etc. to do so it might be a week or so.
I CAN'T WAIT!!!!!!!!!
 

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Okay, I get it, I hadn't considered the thicker shims.

But do you just "drop in" these cams? I'd imagine that you need to adjust ignition and need a bigger throttle body?
 

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But do you just "drop in" these cams? I'd imagine that you need to adjust ignition and need a bigger throttle body?
Pretty much... with every performance mod to engines though there's always another mod that can be done to make the first mod perform better. Such is the life of a modder :)

Dunno if ignition changes would make a much of a difference, obviously fuel metering would be adjusted accordingly; but ignition plays more a part with other things like engine speed & load, and to lesser extent fuel octane.
I've mentioned to Joram before about the very positive change I've gotten from porting and polishing the throttle bodies of mine.
 

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Discussion Starter #59
Okay, I get it, I hadn't considered the thicker shims.

But do you just "drop in" these cams? I'd imagine that you need to adjust ignition and need a bigger throttle body?
They claim to be a drop in with no other work needing to be done to the engine other than maybe a PowerCommander-V.

We will find out soon.....
 

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Dave, are you going to check PTV clearance and coil bind? The additional lift looks to be considerable given the gap that needs to be filled with shim...
 
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