SuzukiSavage.com /cgi-bin/YaBB.pl General Category >> Rubber Side Down! >> Camshaft Comparison /cgi-bin/YaBB.pl?num=1543987585 Message started by DragBikeMike on 12/04/18 at 21:26:25

Title: Camshaft Comparison Post by DragBikeMike on 12/04/18 at 21:26:25 Back in October, I posted a request for loaner cams.  There isn’t much information on the cams that fit the LS650.  I wanted to measure and record the timing data on the available LS650 cams, and also plot the cam curves in ten-degree increments for easy comparison.  I was able to come up with five cams to measure. I had previously posted some timing checks on the stock cam and a DR650 cam (1995 model year), but I measured the timing data at the valve.  The standard practice is to take timing data on the lobe at a predetermined lift.  The SAE checks timing at .006” lobe lift, and various cam manufacturers check at either .020”, .040”, or .050” lobe lift.  The Harley crowd checks at .053” lobe lift.  After sifting through all sorts of literature, I arrived at the conclusion that most of the experts like .050”.  I decided to check cam timing at .020”, .040” and .050” and tabulate that data.  That way it will be easy to compare one of our LS650 cams to any other cam that has timing data at one of those three lifts. All the timing data I tabulate in this post is taken at the lobe, not the valve. In addition to the timing data, I took valve lift data in ten-degree increments and plotted curves to display valve lift in relation to crankshaft position.  The curves allow an easy way to quickly compare one cam to another.  I also measured maximum valve lift and TDC valve lift.  I used the maximum valve lift point to determine lobe centerline, and used that information to calculate lobe separation angle (LSA).  All of the data collected for the cam curves, maximum valve lift, and TDC valve lift, was taken at the valve, not the lobe. I tried my best on all the tables and graphs to identify where the readings were taken.  This was a pretty big job for me and there’s a possibility that I flubbed up a reading or two.  If you are going through this data, and you unearth what appears to be a screw up, please call it out and I will do my best to get it corrected.  That could be tricky because all the loaner cams have been returned.

Title: Re: Camshaft Comparison Post by DragBikeMike on 12/04/18 at 21:28:09 If you have one of the following cams and are willing to trust me with it for a week or two, please send me a PM so we can arrange the transfer.  I borrowed three of the of the cams I measured from Dave, so if you want to verify whether I am reliable, drop Dave a PM.  Here are the cams I still need to test: Web grind 466+2.5°, part number 71-811 Web grind 180, part number 71-831 Web grind 402, part number 70-081 Web grind 340b, part number 70-091 All the data tables and graphs in this post are jpeg files.  I also have the information in PDF.  If you are interested in a PDF, drop me a PM and I will see what I can do.

Title: Re: Camshaft Comparison Post by DragBikeMike on 12/04/18 at 21:38:13 I measured the stock cam, the Web 466, the Web Stage 1, the 1995 DR650, and the Web Stage 3.   The stock cam is obviously a low performance item, and the Web 466 is only slightly more aggressive. The Stage 1 and the DR650 are almost identical, with the DR cam owning a slight edge.  It has more TDC lift and overlap, which should give it a nice mid-range sweet spot.  One possible problem with the DR cam is the intake closing point.  At 34° ABC it is the earliest closing point for any of the five cams measured.  That increases the effective compression stroke and could result in detonation if you increase compression with a pop top piston.  The DR cam also does not incorporate oiling holes in the lobes.  I am currently running the DR cam and am not experiencing any issues with detonation or oiling.  I inspect the lobes periodically and will post any problems I experience on those lines. 11/1/23 I ultimately learned that the oil holes in the cam lobes provide lubrication for the left-hand main bearing and balancer bearing.  I had two main bearing failures before I figured this out.  DO NOT RUN THE DR CAM WITHOUT DRILLING THE OIL HOLES IN THE LOBES AND ENLARGING THE CENTER HOLE ON THE RIGHT-HAND SIDE OF THE CAM. DBM The stage 3 is the most aggressive but looks like it will offer good drivability.  It really doesn’t have any more duration than the DR or Stage 1, has minimal overlap, and relatively low TDC lift.  However, I personally do not consider the Stage 3 a bolt-in cam because of its maximum lift (.393” intake).  With only .430” available travel between the valve spring retainer and the guide seal, the .393” intake lift leaves only .037” clearance between the retainer and seal when the valve is fully open.  You generally want a margin of .060”, so as a minimum, the head should be checked to make sure you won’t have an interference problem with the Stage 3 cam.  I know that some members are running that cam with no problems, but there are manufacturing tolerances to consider.  The consequences of a collision between the retainer and guide are grim at best.  If you don’t plan on doing a proper setup, use the Stage 3 at your own peril. I respectfully invite comments and discussion on this post.  Testimonials to the cam you are running now, or have run in the past, would be great.  Comments on any problems you have experienced with any of these cams, or others not contained herein, will help all of us to avoid serious issues on our projects.  Please share information about setup, springs, retainers, clearance, interference, etc.  It goes without saying that we are all anxious to hear about performance.  How does your cam perform?  Did you have to increase your compression ratio to compensate for late intake closing event?  Fuel octane? Failures?  Loss of low-end performance?  Freeway performance?  Hard starting?  Detonation? It’s all good. Also, if you are aware of any other camshafts that fit the LS650, please share that info.  Even if the cam isn't a bolt in, there may be some members that are willing to perform the necessary mods to accomodate the cam.   Knowledge is power. Best regards, Mike

Title: Re: Camshaft Comparison Post by DragBikeMike on 12/04/18 at 21:40:24 Here is the stock timing data taken at the lobe.

Title: Re: Camshaft Comparison Post by DragBikeMike on 12/04/18 at 21:41:15 Here is the stock valve lift data.

Title: Re: Camshaft Comparison Post by DragBikeMike on 12/04/18 at 21:43:07 Here is the Web 466 timing data.

Title: Re: Camshaft Comparison Post by DragBikeMike on 12/04/18 at 21:44:30 Here is the Web 466 valve lift data.

Title: Re: Camshaft Comparison Post by DragBikeMike on 12/04/18 at 21:45:55 Here is the graph of the stock intake lobe vs the Web 466.

Title: Re: Camshaft Comparison Post by DragBikeMike on 12/04/18 at 21:47:25 Here is the graph of the stock exhaust lobe vs the Web 466.

Title: Re: Camshaft Comparison Post by DragBikeMike on 12/04/18 at 21:48:35 Here is the Stage 1 timing data.

Title: Re: Camshaft Comparison Post by DragBikeMike on 12/04/18 at 21:49:35 Here is the Stage 1 valve lift data.

Title: Re: Camshaft Comparison Post by DragBikeMike on 12/04/18 at 21:51:52 Here is the graph of the Stage 1 intake vs Stock.

Title: Re: Camshaft Comparison Post by DragBikeMike on 12/04/18 at 21:52:57 Here is the graph of the Stage 1 exhaust vs stock.

Title: Re: Camshaft Comparison Post by DragBikeMike on 12/04/18 at 21:54:38 Here is the DR650 timing data.

Title: Re: Camshaft Comparison Post by DragBikeMike on 12/04/18 at 21:55:36 Here is the DR650 valve  lift data.

Title: Re: Camshaft Comparison Post by DragBikeMike on 12/04/18 at 21:56:51 Here is the graph of the DR 650 intake vs stock.

Title: Re: Camshaft Comparison Post by DragBikeMike on 12/04/18 at 21:57:48 Here is the graph of the DR650 exhaust vs stock.

Title: Re: Camshaft Comparison Post by DragBikeMike on 12/04/18 at 21:58:38 Here is the stage 3 timing data.

Title: Re: Camshaft Comparison Post by DragBikeMike on 12/04/18 at 21:59:18 Here is the stage 3 valve lift data.

Title: Re: Camshaft Comparison Post by DragBikeMike on 12/04/18 at 22:00:51 Here is the graph of the stage 3 intake vs stock intake.

Title: Re: Camshaft Comparison Post by DragBikeMike on 12/04/18 at 22:02:02 Here is the graph of the stage 3 exhaust vs stock exhaust.

Title: Re: Camshaft Comparison Post by DragBikeMike on 12/04/18 at 22:05:42 I think this is a lot of useful info.  As I mentioned earlier. I look forward to your comments.

Title: Re: Camshaft Comparison Post by Ruttly on 12/05/18 at 10:13:13 Nice work , now we just need corresponding dyno reports to over lay the H/P & torque output onto your graph. Wouldn't be nice if it was dohc and so cam timing was adjustable for each cam, then we could make H/P on the cheap. I had a SR500 that had adjustable cam timing. Add a cam , great , being able to adjust/degree it , priceless ! That bike had a downright scary midrange ! But you also need the ability to change ignition timing as well .

Title: Re: Camshaft Comparison Post by Ruttly on 12/05/18 at 20:21:52 I remember doing a similar graph for my last SR 500. Most people used v blocks to support the cam , I used the head it took hours to get it written down and even longer to make the graph. It was a real task. One thing is for sure , we have a registered,card carrying gear head on the loose here at SS ! Keep up the good work DBM , some here are learning from this and  I am recalling all the steps it takes to know what you are doing when building an engine , it's been 25+ years since I have done all this stuff. Building my engine was all from experience of the 20+ motorcycle engines I have built , every trick I know went into this engine but none of the math. Did some math on the intake but it only made small differences after a lot of time experimenting and money spent. Was only able to improve performance at a small rpm range and move that range up & down.

Title: Re: Camshaft Comparison Post by LANCER on 12/06/18 at 04:32:45 I agree, I am very appreciative of the desire to share with the rest of us the knowledge and skills in determining all of the details that have been shared on these threads. THANK YOU !

Title: Re: Camshaft Comparison Post by sparktfxr on 12/24/18 at 15:54:30 Hi..fantastic info and would like to add my findings with my 2014 S40, recently fitted a stock DR cam (which I drilled the oil holes in quite easily) and set the timing as per the specs for a DR measured at .040" lift which is io 6 BTDC / ic 49 ABDC / eo 46 BBDC / ec 12 ATDC. I do have the slightly taller gearing with the Kawasaki drive sprocket, different exhaust, 96mm wiseco 9.1/1 piston, altered porting but the original CV carby  & ..the bike ran OK & I did about 300km like this but felt a bit flat so advanced the cam about 9 deg by advancing on the crank sprocket then retarding the cam sprocket (I think thats right) so the io 15 BTDC & eo 55 BBDC...It felt better, pulls strongly from low down to about 4500rpm but then falls off & can't get it to rev much past 5... but as is still great fun to ride Am experimenting with a mikuni round slide & different filters also with exhaust systems but so far can't seem get the motor to rev. A motorcycle mechanic friend suggested that the flat face of the "D"shaped exhaust port is used by some manufacturers to improve low down torque but inhibits the fine tuning of the ex/system for the benefit of the incoming fuel charge as the returning pulse is stopped when it hits this wall. Doesn't matter if theres no overlap like the stock cam but restricts your options. Also it would be great to somehow get the benefits of some squish effect in this motor, the distance between the piston top & the head is big & a piston with more meat above the gudgeon could be worth a try, flat topped would be a good start to take advantage of squish. Ive seen a wiseco Yamaha 660 but can't yet find all the needed info.. anyhow the search for improvement goes on.... & the Christmas lunch awaits...so All the best for the season to you all

Title: Re: Camshaft Comparison Post by batman on 12/24/18 at 22:14:11 It seems illogical that the pressure wave created at the valve opening and passing through the D shaped opening in the exhaust passage  would be stopped on it's return. It 's more likely that the DR cam is of poor design for use in the Savage/S-40 motor.

Title: Re: Camshaft Comparison Post by LANCER on 12/25/18 at 04:12:27 There is a drastic difference in the exhaust ports in DR vs LS. THE DR’s exhaust ports are wide open just like the intake.

Title: Re: Camshaft Comparison Post by sparktfxr on 12/25/18 at 14:48:36 Ive tried exhaust combos with both the stock & DR cam & yes I agree the DR cam  isn't a perfect cam but the options are bit limited especially being a single cam. I dont have any measured data but the DR cam seems to give my bike a bit more grunt...which is good. We have a company down here who have been making cams for 2 generations who I contacted & they said to send them all the info & what I want from the motor.. so I might do that next year & get their opinion

Title: Re: Camshaft Comparison Post by batman on 12/26/18 at 00:11:40 You would be better of obtaining a stage 3 cam from LANCER.

Title: Re: Camshaft Comparison Post by DragBikeMike on 12/26/18 at 13:01:50 Spartfxr, I think you should re-time your DR cam to the factory marks.  The DR cam closes the intake earlier than the stock cam.  Advancing the timing aggravates that condition.  Closing the intake so early is limiting your powerband, causing the engine to fall flat on it's face at 4500 rpm.   With the DR cam, my engine pulls hard all the way to 6500 rpm.  The cam is set to the stock timing marks.   Check the dyno curve I have attached to this post.  You will see that the DR cam results in a nice broad power band that does not sign-off at 4500.   I wouldn't use the ProCycle timing data (that you discussed in an earlier post) because the cam they offer is for a 1996 and later DR650, which uses a different cam (it won't fit our LS650 engine).

Title: Re: Camshaft Comparison Post by kojones on 12/27/18 at 10:40:26 Thanks DragBikeMike, you've provided excellent and easily understandable data about the camshafts. I need to get a Savage again, kinda miss mine. I'd like to try a stock DR piston in a LS, they're quite a bit cheaper than Wisecos.

Title: Re: Camshaft Comparison Post by DragBikeMike on 11/13/19 at 00:41:08 I procured two more Web cams, the 402 grind and the 340b grind.  They are both aggressive camshafts and are not bolt in cams.  As a minimum, they will require cutting/shortening the valve guides to achieve adequate clearance between the spring retainer and guide seal, and installation of stiffer springs with more available travel.  The stock springs approach coil-bind at the higher lifts these cams provide. There has been some discussion recently about the merits of the higher lift.  I thought I would elaborate on that in this update.  There is a rule of thumb that maximum flow is achieved once a valve reaches a lift that equals 25% of its diameter.  Our intake valves are 1.3” diameter, so that rule of thumb would dictate that max flow should be about .325” lift.  My flow bench tests confirm that.  The flow starts to flatten out at .325” lift.  It increases a bit from .325” up to .400”, but it’s a very shallow curve.  I think its safe to say that the rule of thumb is accurate.  You’re not gonna gain much by opening the valve farther than .325” (25% of valve diameter). The benefit of the additional lift isn’t the increase in valve opening, it is the length of time (in degrees crankshaft rotation) that the valve is at or above the max flow lift.

Title: Re: Camshaft Comparison Post by DragBikeMike on 11/13/19 at 00:43:22 The stock cam achieves .325” intake lift at about 80° BBC and holds the valve at or above .325” lift until about 30° BBC.  That’s 50° of crankshaft rotation. The DR650 cam achieves .325” intake lift about 70° ATC and holds the valve at or above .325” lift until about 35° BBC.  That’s 75° of crankshaft rotation. The Web 402 grind cam achieves .325” intake lift at about 50° ATC and holds the valve at or above .325” lift until about 25° BBC.  That’s 105° of crankshaft rotation. The Web 340b grind cam achieves .325” intake lift at about 35° ATC and holds the valve at or above .325” lift until about 25° BBC.  That’s 120° of crankshaft rotation. Although the flow is not increasing much once the valve reaches .325” lift, it’s still flowing the maximum the port & valve will allow.  Increasing the amount of time that the valve is at or above the max flow position is most certainly increasing cylinder fill.  The 340b grind holds the valve at or above .325” 70° longer than the stock cam.  It more than doubles the time at max flow lift.

Title: Re: Camshaft Comparison Post by DragBikeMike on 11/13/19 at 00:44:43 It would be nice if the cam simply held the valve at .325” for a longer period.  That way, you wouldn’t need to fiddle around with the guides, and the stock springs wouldn’t go into coil-bind.  Alas, its not that simple.  The cam must incorporate acceleration & deceleration ramps.  The rocker arm and valve motion just can’t be stopped abruptly.  Just as you can’t allow the valve to slam into the seat when it closes, you also can’t expect it to change direction abruptly from opening to closing.  The cam must start slowing things down as the valve approaches full open, otherwise the rocker arm will loft off the cam lobe and you will lose control of the valve.  In order to keep the valve at max flow lift for a longer period, the cam has a deceleration ramp.  The deceleration ramp is in the portion of the lobe profile that opens the valve past max flow lift.

Title: Re: Camshaft Comparison Post by DragBikeMike on 11/13/19 at 00:45:40 Regarding the protocol used herein to measure and record cam timing, Web does not follow the convention I am using.  Earlier in the post, I stated that I would be using lobe lift for the timing data, and valve lift for the curves.  Unlike all the other cam manufacturers that I have dealt with in the past, and researched for this post, Web takes their timing data at the valve.  The Web data is not gonna agree with my data.  To make things even more interesting, the DR650 uses different rocker arms.  The DR part numbers are different from the LS, so there’s no way to know that the rocker ratios are the same.  The rocker ratio will certainly have a big impact on when the valve opens, and how far it opens.  I suspect that’s why my data doesn’t agree with Web’s data sheets. The graphs I did for the 402 grind and the 340b grind compare the new cams to the stock DR650 cam.  Since I’m currently running the DR cam the comparison was more appropriate for my purposes.  Don’t get confused by the graphs.  If you want to see how the new grinds compare to a stock cam, you will have to plot your own graphs.  All the data you will need is in this post.

Title: Re: Camshaft Comparison Post by DragBikeMike on 11/13/19 at 00:49:04 Here is the Web 402 timing data taken at the lobe.

Title: Re: Camshaft Comparison Post by DragBikeMike on 11/13/19 at 00:49:52 Here is the Web 402 valve lift data.

Title: Re: Camshaft Comparison Post by DragBikeMike on 11/13/19 at 00:51:04 Here is a graph of the Web 402 intake compared to the stock DR650 intake.

Title: Re: Camshaft Comparison Post by DragBikeMike on 11/13/19 at 00:51:59 Here is a graph of the Web 402 exhaust compared to the stock DR650 exhaust.

Title: Re: Camshaft Comparison Post by DragBikeMike on 11/13/19 at 00:52:55 Here is the Web 340b timing data taken at the lobe.

Title: Re: Camshaft Comparison Post by DragBikeMike on 11/13/19 at 00:53:40 Here is the Web 340b valve lift data.

Title: Re: Camshaft Comparison Post by DragBikeMike on 11/13/19 at 00:54:33 Here is a graph of the Web 340b intake compared to the Stock DR650.

Title: Re: Camshaft Comparison Post by DragBikeMike on 11/13/19 at 00:55:25 Here is a graph of the Web 340b exhaust compared to the stock DR650.

Title: Re: Camshaft Comparison Post by DragBikeMike on 11/13/19 at 01:07:06 I think these two additional cams provide us with some interesting options.  They are not bolt in cams.  The cylinder head must be removed in order to install either cam properly.  All clearances must be verified.  They will require some minor machining and the added expense of stiffer springs.  In addition, the DR650 spring kit is not directly applicable to the LS.  The spring retainers and cotters can't be used on the LS.  With a little research and patience, I'm sure the problems can be solved. The timing and lift data I have provided should be helpful if you are considering a big cam upgrade.  I hope you find it useful. Knowledge is power.

Title: Re: Camshaft Comparison Post by batman on 11/14/19 at 01:19:56 If you're running a stock bike , the Web Cam Inc. -466 Cam, is better  than the stock cam.   The  .325 opening of the valve allowed by the stock cam is 25% of the intake valve's diameter, but doesn't take into account the area taken up by the valve's stem, making the valve lift of the intake ,  slightly less than ideal. The 466 also lifts the exhaust valve farther off seat so as to not block the exhaust valve port .

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