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Old 12-07-2012, 08:36 PM   #16
supershaft
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Those specs are probably taken at 0 lift. I know from experimenting with a Rotax cam (with much longer ramps than many cams made for the engine) that just a few thousandths of an inch can equate a lot of degrees at the crank. The end result was a short track bike that was a LOT easier to get started at the track! As far as I understand the process, no manufacture can even come close to guaranteeing timing just off the round of the cam. It is impossible to grind them that accurately right there. That's the whole reason for the check point. How fast they open a valve? That depends on what lift check point they use. The higher the check point, the more revealing it becomes in that regard. Then, of course, you can time the cam yourself and know exactly how the cam is opening the valve.
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Old 12-07-2012, 08:50 PM   #17
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Quote:
Originally Posted by supershaft View Post
Those specs where pulled up for the previous cam thread. They have no check point. The specs given pretty much have to have no check point if I remember right. Specs with no check point are just about useless. That's why Crane to Megacycle lists a check point with their specs. Unfortunately, there is no standardized check point that the cam industry uses. Since the check point itself drastically changes the specs, there is software out there that will compare specs with difference lift check points. Check points are crucial for comparing grinds, timing grinds, and checking grinds in order to make sure that your cam is indeed timed as it is suppose to be.
Correct. I posted this in a previous thread and they came from Motoren Isreal.
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Old 12-08-2012, 04:14 AM   #18
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I'm wondering what the goal of this fruitless discussion is.
You are discussing incomplete data a reseller provides and are complaining they are incomplete and thus useless.
And blame the manufacturer and the product for that.

Does that make sense?

The only way to find out if the information the manufacturer provides come up to your standards would be to get the information directly from there, study them and judge then.
This way everyone here would benefit.
And the effort for that would really be minimal.

Everything else has the bad taste as if motivation for this discussion is something completely different.
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Old 12-08-2012, 06:11 AM   #19
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I believe what you are referring to is known as self-aggrandizement
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Old 12-08-2012, 07:03 AM   #20
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I think that we are all agreed that if SS needs further information about the various cams he needs to contact the manufactures oirect and ask them nicely. I'm sure that they will reply in English. I seem to remember that contact details are in the previous cam thread.

Meanwhile I will let the dyno do the talking, in that we will have before and after cam change figures on my R90/6. I won't be making any other alterations to the bike. Yes I know that the same bike on the same dyno on different runs will give slightly different figures, but the odd BHP here or there is immaterial, I'm interested in seeing how the cam changes the power delivery from the engine, so I would hope to increase in torque over a wide rev band.

For those who are interested, the bike was fully rebuilt just under 2 years ago, it is stock apart for 10.1 Wossner lightweight pistons, dual plugged with a Sachse ignition, a lightened flywheel and it has had the ports cleaned up. The engine was balanced Carbs and exhaust are stock. The bike runs very well at the moment.

It might well be that I will change the camshaft and will think that it's really brilliant, goes like a MOFO etc etc, but if the dyno says not much of a change, then I will just have to accept that the reality was that this cam change did not make much of a material change to how the bike performs!
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Old 12-08-2012, 11:14 AM   #21
supershaft
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Quote:
Originally Posted by RGregor View Post
I'm wondering what the goal of this fruitless discussion is.
You are discussing incomplete data a reseller provides and are complaining they are incomplete and thus useless.
And blame the manufacturer and the product for that.

Does that make sense?

The only way to find out if the information the manufacturer provides come up to your standards would be to get the information directly from there, study them and judge then.
This way everyone here would benefit.
And the effort for that would really be minimal.

Everything else has the bad taste as if motivation for this discussion is something completely different.
What are you on RG? The goal of this fruitless discussion is to find some meaningful specs so that those of us that are interested in performance cams can compare the cams available without buying every one of them. I am very interested in performance cams for one. Motivation? Where do you guys get off? I know: WAY back.

Some of us here have reported buying a number of these cams or even timing dozens of them. Surely someone has called for the cam's specs with a check point or has done enough cams to figure out a check point? The effort to report their findings here would be minimal indeed.

Otherwise, get off my back for pointing out that those specs are just about useless for comparison or setup without a check point. I don't have very much cam experience but I do know enough to start at the beginning. And it's giving a bunch of you guys a headache? To the point of trying to make up why I am trying to find some meaningful cam specs other than finding some meaningful specs? I have already emailed them and got the same stuff everyone has already seen. Call them? You are in the same country and already have some of their cams! But first you need to understand why and how specs with a check point are essential before you can meaningfully ask for them. That I have TRIED to explain and what do I get in return? This crap!

supershaft screwed with this post 12-08-2012 at 11:39 AM
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Old 12-08-2012, 01:08 PM   #22
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Quote:
Originally Posted by supershaft View Post
Call them? You are in the same country and already have some of their cams! But first you need to understand why and how specs with a check point are essential before you can meaningfully ask for them. That I have TRIED to explain and what do I get in return? This crap!
Sorry but, what you get back has something to do with the way you lead your discussions when it's about cams.
I remember well the cam thread. I just was the messenger, that the 336 was not used over here and literary found myself in front of a cam-tribunal with you as the main inquisitor and the unvisible crowd (your words) in the back.

And now I learn this was simply because you TRIED to explain the meaning and importance of a check point to me so that I could ask Schleicher for the missing information? Sorry man but, I must have missed that.

Personally I did not get the impression that you are interested in performance cams as you already seem to have found one answer for all questions regarding cams.

So if you're really interested, what do you suggest?
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Old 12-08-2012, 04:29 PM   #23
supershaft
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Quote:
Originally Posted by RGregor View Post
Sorry but, what you get back has something to do with the way you lead your discussions when it's about cams.
I remember well the cam thread. I just was the messenger, that the 336 was not used over here and literary found myself in front of a cam-tribunal with you as the main inquisitor and the unvisible crowd (your words) in the back.

And now I learn this was simply because you TRIED to explain the meaning and importance of a check point to me so that I could ask Schleicher for the missing information? Sorry man but, I must have missed that.

Personally I did not get the impression that you are interested in performance cams as you already seem to have found one answer for all questions regarding cams.

So if you're really interested, what do you suggest?
Concerning cams? I just wrote that in my last thread.

Otherwise, put me on your ignore list so you will quit bogging down this discussion with your psycho analysis of my motivations. After all, there are about five of us here who would love to get some usable specs without all the BS.
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Old 12-09-2012, 04:59 AM   #24
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Quote:
Originally Posted by supershaft View Post
Concerning cams? I just wrote that in my last thread.

Otherwise, put me on your ignore list so you will quit bogging down this discussion with your psycho analysis of my motivations. After all, there are about five of us here who would love to get some usable specs without all the BS.
Just an idea to get comparable specs:
The Schleicher data are theoretical data including the ramps, the BMW specs are given with respect to preload and additional lift, resulting in a measurable duration of 264 and the following timing.

AO AS EO ES
52 32 32 52

The theoretical duration of the 336 is probably 336.
So if we add (336-264)/2 to the BMW spec we get

AO AS EO ES
88 68 68 88

Very near the Schleicher 332 profile.
Lobe center would be 100. That would be reasonable.
We know that valve lift with the 336 is 10.68mm, so cam lift is 7.79mm
Lift at overlap probably is a bit higher than that of the 332 (3.7mm)
For the later version of the 336 you'll have to shift it 3.

Comparing that with the Schleicher data it seems plausible.

Still no check point to check the grind but probably comparable specs.

Edit:
AO: exhaust opens
AS: exhaust closes
EO: intake opens
ES: intake closes

RGregor screwed with this post 12-09-2012 at 08:44 AM Reason: Added some explanation
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Old 12-09-2012, 10:02 AM   #25
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I've been following this thread and the cam thread for some time so I decided to do some research of my own. The motor I'm using as my street rod was built from the outset with the 336 BMW cam. At that time [1980] the only options were the Crane, Andrews and Erson regrinds which I stayed away from as I was worried about excessive acceleration rates and wear problems. When I had the heads flowed and ported the flow bench operator mentioned that the cam specs. that he measured were quite old fashioned and I could obtain better results with something newer. I let this slide until a few years ago, when I came across the Israel website. I substituted the 336 that I was using in the racer and noticed an improvement with the 344 that I installed. This is not a good street cam if you want low speed driveability but on the track, it was an improvement. Fast forward to last month when I started to install the 324 in the streeter. To check the cam specs., I built a dummy motor with post 81 clutch carrier and single row camchain. The results were 65/35,33/65.measured at 1.0MM lift. Once I've built this motor, I'll do the specs. on the 344, 330, Schleicher cams 336BMW and 320BMW cams. As an aside, the figures can be altered simply by adjusting the valves a bit looser or tighter than stock. Also, with heavy duty springs, there will be a certain amount of camshaft flexure as the lobes do not lie in opposing planes so the loading is cyclical. The pushrods flexing at high revs will also affect valve timing the only fix for this being to install chrome-moly rods which I have done. My results were from many repeats of the measurements including verification of true TDC mark on the flywheel which turned out to be correct. My use of the single chain and tensioner also meant that the 3Deg advance was included. My conclusion from all this is that this cam is ground with the later offset in mind as it can be installed without an offset key to achieve the symetrical timing these motors like. Darn, I had a set of keys made up in anticipation of needing them. I will post the figures for the other cams in the not too distant future. I hope this helps the discussion.
Cheers
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Old 12-09-2012, 10:50 AM   #26
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Quote:
Originally Posted by supershaft View Post
Those specs where pulled up for the previous... [snip]
...in order to make sure that your cam is indeed timed as it is suppose to be.
Ok, where is your website? Where are your specs? What information have you made available?

Sheesh.

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Old 12-09-2012, 12:17 PM   #27
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Quote:
Originally Posted by 983Bob View Post
I substituted the 336 that I was using in the racer and noticed an improvement with the 344 that I installed. This is not a good street cam if you want low speed driveability but on the track, it was an improvement.
Hello Bob!

The 344 and the 332 AFAIK are very old profiles from the early 60ies, developed for the car engines (BMW 700).
The 344 is often mentioned as "the" race cam over here.
A friend has one in his street bike and after a look at his torque curve I would share your opinion.
A big boost above 5k but mid range suffers (although still in the 80+Nm range). Maybe good for open road, but not good for twisty roads like in the alps.
The 324 and even more the 320 are popular cams for road use.

Please keep us informed about your results with the 324.

Regards,

Rudi
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Old 12-09-2012, 12:36 PM   #28
supershaft
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Quote:
Originally Posted by 983Bob View Post
I've been following this thread and the cam thread for some time so I decided to do some research of my own. The motor I'm using as my street rod was built from the outset with the 336 BMW cam. At that time [1980] the only options were the Crane, Andrews and Erson regrinds which I stayed away from as I was worried about excessive acceleration rates and wear problems. When I had the heads flowed and ported the flow bench operator mentioned that the cam specs. that he measured were quite old fashioned and I could obtain better results with something newer. I let this slide until a few years ago, when I came across the Israel website. I substituted the 336 that I was using in the racer and noticed an improvement with the 344 that I installed. This is not a good street cam if you want low speed driveability but on the track, it was an improvement. Fast forward to last month when I started to install the 324 in the streeter. To check the cam specs., I built a dummy motor with post 81 clutch carrier and single row camchain. The results were 65/35,33/65.measured at 1.0MM lift. Once I've built this motor, I'll do the specs. on the 344, 330, Schleicher cams 336BMW and 320BMW cams. As an aside, the figures can be altered simply by adjusting the valves a bit looser or tighter than stock. Also, with heavy duty springs, there will be a certain amount of camshaft flexure as the lobes do not lie in opposing planes so the loading is cyclical. The pushrods flexing at high revs will also affect valve timing the only fix for this being to install chrome-moly rods which I have done. My results were from many repeats of the measurements including verification of true TDC mark on the flywheel which turned out to be correct. My use of the single chain and tensioner also meant that the 3Deg advance was included. My conclusion from all this is that this cam is ground with the later offset in mind as it can be installed without an offset key to achieve the symetrical timing these motors like. Darn, I had a set of keys made up in anticipation of needing them. I will post the figures for the other cams in the not too distant future. I hope this helps the discussion.
Cheers
Bob
NOW we are getting somewhere! For those of you that are trying to psycho analyse my motivations: This is why I am here!

@Bill: I don't have any specs. That is why I am looking for some! I could pull some out of my ass that add to 360 but that would get us exactly where we were to start with. But some are happy with BS. Look at the idiotnet!

@bob: I am pretty sure BMW had a 'race' cam and the 336 available at least in the seventies. Megacycle had one too in '80? Anyway, thanks SO much.

Which cam is 65/35,33/65? AT 1mm!!! (Thanks again!)

Sure just a few thousandths at a valve makes a big difference at the crank particularly on cams with long ramps. My advise is to forgo the entire setup. Check timing at the lifter. The engine is easier to turn and there is NO flex, NO ratios, and NO radii involved (they are ROCKER arms, not pistons!). Leave your test engine down to the crank and cam!

I have always suspected BMW's TDC's were close because I almost never have a piston blow back during leak downs unlike many other brands. Timing cams? I would still find TDC with a piston stop and a degree wheel. We're timing cams. Just one degree matters!

Despite all the crap on this forum, it can still rock! Thanks again so much Bob!

supershaft screwed with this post 12-09-2012 at 01:25 PM
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Old 12-09-2012, 01:13 PM   #29
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I have a feeling that the 336 was the early 70s BMW race cam"."................. Full circle guys!

Bob, thanks for your input, it will be useful to get your results.
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Old 12-09-2012, 01:18 PM   #30
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Quote:
Originally Posted by chasbmw View Post
I have a feeling that the 336 was the early 70s BMW race cam"."................. Full circle guys!

Bob, thanks for your input, it will be useful to get your results.
No, it wasn't. The 336 has always been called the "sport" cam. I believe there was a "race" cam available too AT THE SAME TIME as the 336 was available from B+S and later BMWNA too if I remember right.

Full circle? MI and Siebenrock cams with real, usable specs? It's a first as far as I know!

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