KLX 250 ( 300 ) camshaft mod by Marcelino
#362
06-24-2012 | 03:49 PM
Member
1st Gear Member
Joined: Apr 2012
Posts: 32
From: SW Georgia
The numbers I used in my last post were all at .050" lift, but I also took the numbers from point of lift to point of closure, and they didn't match Kawasaki numbers either.
My readings on point of lift matched Kawasaki's published figures, but the point of closure were more than 15 deg later
with Marcelino mod
intake opens at 33 BTDC and closes at 65 ABDC
stock config would be 21.5 open and 76.5 closed
exhaust opens at 49 BBDC and closes at 45 ATDC
stock config would be 60.5 open and 56.5 closed
The reason I didn't list these numbers earlier is that the closing ramps have such a gentle slope that I didn't think anyone would believe my readings. (not sure I believe them either)
The last 10-15 mils of closure is more than 15 degrees of crank rotation.
The only logic I can put to this is Kawasaki wants the valves to close very softly.
I first thought that I had a bad cams, but both cams are milled the same, so.....................
.
My readings on point of lift matched Kawasaki's published figures, but the point of closure were more than 15 deg later
with Marcelino mod
intake opens at 33 BTDC and closes at 65 ABDC
stock config would be 21.5 open and 76.5 closed
exhaust opens at 49 BBDC and closes at 45 ATDC
stock config would be 60.5 open and 56.5 closed
The reason I didn't list these numbers earlier is that the closing ramps have such a gentle slope that I didn't think anyone would believe my readings. (not sure I believe them either)
The last 10-15 mils of closure is more than 15 degrees of crank rotation.
The only logic I can put to this is Kawasaki wants the valves to close very softly.
I first thought that I had a bad cams, but both cams are milled the same, so.....................
.
Last edited by John65; 06-24-2012 at 08:41 PM.
#363
06-24-2012 | 03:57 PM
Member
1st Gear Member
Joined: Apr 2012
Posts: 32
From: SW Georgia
The specs are the same on all of them...
#364
06-24-2012 | 04:17 PM
Member
1st Gear Member
Joined: Apr 2012
Posts: 32
From: SW Georgia
As I stated earlier, I love the low end torque that I have with this mod, but the carb tuning has totally whipped me.
Everything I've read says that I would need to jet richer, so I did and the bike won't run at full throttle under 5000 rpm. I'm now back to my original jetting (38 pilot, 25 mil shim under stock needle, and 132 main jet), and it still acts like it's way too rich.
The plug reading is porcelin is light brown and ground electrode is clean, but the base ring is sooty, which says I'm too rich. At full throttle under 5000, it sputters and misfires like an old 2 stroke with 3 sizes too large a main jet.
I don't have a new plug on hand now, but my next change will be to try a new plug (maybe it just won't fire under that much compression pressure)
I used to think I was a good tuner, but now (I'm really frustrated!!!!!)
Everything I've read says that I would need to jet richer, so I did and the bike won't run at full throttle under 5000 rpm. I'm now back to my original jetting (38 pilot, 25 mil shim under stock needle, and 132 main jet), and it still acts like it's way too rich.
The plug reading is porcelin is light brown and ground electrode is clean, but the base ring is sooty, which says I'm too rich. At full throttle under 5000, it sputters and misfires like an old 2 stroke with 3 sizes too large a main jet.
I don't have a new plug on hand now, but my next change will be to try a new plug (maybe it just won't fire under that much compression pressure)
I used to think I was a good tuner, but now (I'm really frustrated!!!!!)
Last edited by John65; 06-24-2012 at 04:33 PM.
#365
06-25-2012 | 01:40 AM
Senior Member
Joined: Mar 2009
Posts: 333
From: Quebec, Canada
1st Gear Member
The numbers I used in my last post were all at .050" lift, but I also took the numbers from point of lift to point of closure, and they didn't match Kawasaki numbers either.
My readings on point of lift matched Kawasaki's published figures, but the point of closure were more than 15 deg later
with Marcelino mod
intake opens at 33 BTDC and closes at 65 ABDC
stock config would be 21.5 open and 76.5 closed
exhaust opens at 49 BBDC and closes at 45 ATDC
stock config would be 60.5 open and 56.5 closed
The reason I didn't list these numbers earlier is that the closing ramps have such a gentle slope that I didn't think anyone would believe my readings. (not sure I believe them either)
The last 10-15 mils of closure is more than 15 degrees of crank rotation.
The only logic I can put to this is Kawasaki wants the valves to close very softly.
I first thought that I had a bad cams, but both cams are milled the same, so.....................
.
My readings on point of lift matched Kawasaki's published figures, but the point of closure were more than 15 deg later
with Marcelino mod
intake opens at 33 BTDC and closes at 65 ABDC
stock config would be 21.5 open and 76.5 closed
exhaust opens at 49 BBDC and closes at 45 ATDC
stock config would be 60.5 open and 56.5 closed
The reason I didn't list these numbers earlier is that the closing ramps have such a gentle slope that I didn't think anyone would believe my readings. (not sure I believe them either)
The last 10-15 mils of closure is more than 15 degrees of crank rotation.
The only logic I can put to this is Kawasaki wants the valves to close very softly.
I first thought that I had a bad cams, but both cams are milled the same, so.....................
.
But... is your valve clearance within spec? The nominal clearance at intake is only 6mil, if you have smaller than that it may influence somewhat the closing angle, given that very slow ramp. I suspect even the normal 4 to 7.5mil range may change greatly the closing angle.
On the exhaust side the normal clearance is 6 to 9.5mil, also enough probably to change significantly the closing angle.
Anyway, the 50mil reference is more meaningful, and I guess more reproductible.
#366
06-25-2012 | 01:48 AM
Senior Member
Joined: Mar 2009
Posts: 333
From: Quebec, Canada
1st Gear Member
... How are they different?
#367
06-25-2012 | 09:12 AM
Senior Member
1st Gear Member
Joined: Jun 2010
Posts: 183
Well, first of all say that I think all the data that specifies Kawasaki, so personally I prefer to check things.
In this picture we are left camshaft klx250EFI of 2009
On the right camshaft for a KLX300 2000. Theoretically it is the same as the 250cc installed until 2007. They were the same reference.
Klx300 cam 33'30mm measured high, while the 2009 measures 33'20mm EFI
But most important is that the EFI cam 2009 has a broader curve, wider. Therefore remain open longer.
In summary, the cam 2009 pushes the valve 0'10mm less, but more time remains open.
I tested the cam KLX300 (2000) in my 2009EFI increased engine capacity to 300cc and power achieved is slightly lower than the standard cam. (Always with the changes made Marcelino complete). The feeling is that the cams 2009 are less steep and allows to have a full engine that drives more and better before but the difference is not exaggerated. There are no miracles.
In my opinion, if I had a KLX250 KLX300 or prior to the year 2007 would prove to set you cams, 2009, I think the use and improves engine performance. But I can assure you. Since then at me if I work best cams 2009.
Visually it is almost imperceptible, but on the bike itself noticeable difference disappears as a dip or bump in the medium rpm.
In this picture we are left camshaft klx250EFI of 2009
On the right camshaft for a KLX300 2000. Theoretically it is the same as the 250cc installed until 2007. They were the same reference.
Klx300 cam 33'30mm measured high, while the 2009 measures 33'20mm EFI
But most important is that the EFI cam 2009 has a broader curve, wider. Therefore remain open longer.
In summary, the cam 2009 pushes the valve 0'10mm less, but more time remains open.
I tested the cam KLX300 (2000) in my 2009EFI increased engine capacity to 300cc and power achieved is slightly lower than the standard cam. (Always with the changes made Marcelino complete). The feeling is that the cams 2009 are less steep and allows to have a full engine that drives more and better before but the difference is not exaggerated. There are no miracles.
In my opinion, if I had a KLX250 KLX300 or prior to the year 2007 would prove to set you cams, 2009, I think the use and improves engine performance. But I can assure you. Since then at me if I work best cams 2009.
Visually it is almost imperceptible, but on the bike itself noticeable difference disappears as a dip or bump in the medium rpm.
#368
06-25-2012 | 02:48 PM
Member
1st Gear Member
Joined: Apr 2012
Posts: 32
From: SW Georgia
Yes, soft closing is easier on the valves, and it might be the reason for those long closing ramps.
But... is your valve clearance within spec? The nominal clearance at intake is only 6mil, if you have smaller than that it may influence somewhat the closing angle, given that very slow ramp. I suspect even the normal 4 to 7.5mil range may change greatly the closing angle.
On the exhaust side the normal clearance is 6 to 9.5mil, also enough probably to change significantly the closing angle.
Anyway, the 50mil reference is more meaningful, and I guess more reproductible.
But... is your valve clearance within spec? The nominal clearance at intake is only 6mil, if you have smaller than that it may influence somewhat the closing angle, given that very slow ramp. I suspect even the normal 4 to 7.5mil range may change greatly the closing angle.
On the exhaust side the normal clearance is 6 to 9.5mil, also enough probably to change significantly the closing angle.
Anyway, the 50mil reference is more meaningful, and I guess more reproductible.
while I had the cams out, I checked the shims so that I would know what sizes to get when valves need adjustment, and none of them have numbers on them.
Last edited by John65; 06-25-2012 at 03:12 PM.
#369
06-25-2012 | 03:02 PM
Member
1st Gear Member
Joined: Apr 2012
Posts: 32
From: SW Georgia
Well, first of all say that I think all the data that specifies Kawasaki, so personally I prefer to check things.
In this picture we are left camshaft klx250EFI of 2009
On the right camshaft for a KLX300 2000. Theoretically it is the same as the 250cc installed until 2007. They were the same reference.
Klx300 cam 33'30mm measured high, while the 2009 measures 33'20mm EFI
But most important is that the EFI cam 2009 has a broader curve, wider. Therefore remain open longer.
In summary, the cam 2009 pushes the valve 0'10mm less, but more time remains open.
I tested the cam KLX300 (2000) in my 2009EFI increased engine capacity to 300cc and power achieved is slightly lower than the standard cam. (Always with the changes made Marcelino complete). The feeling is that the cams 2009 are less steep and allows to have a full engine that drives more and better before but the difference is not exaggerated. There are no miracles.
In my opinion, if I had a KLX250 KLX300 or prior to the year 2007 would prove to set you cams, 2009, I think the use and improves engine performance. But I can assure you. Since then at me if I work best cams 2009.
Visually it is almost imperceptible, but on the bike itself noticeable difference disappears as a dip or bump in the medium rpm.
In this picture we are left camshaft klx250EFI of 2009
On the right camshaft for a KLX300 2000. Theoretically it is the same as the 250cc installed until 2007. They were the same reference.
Klx300 cam 33'30mm measured high, while the 2009 measures 33'20mm EFI
But most important is that the EFI cam 2009 has a broader curve, wider. Therefore remain open longer.
In summary, the cam 2009 pushes the valve 0'10mm less, but more time remains open.
I tested the cam KLX300 (2000) in my 2009EFI increased engine capacity to 300cc and power achieved is slightly lower than the standard cam. (Always with the changes made Marcelino complete). The feeling is that the cams 2009 are less steep and allows to have a full engine that drives more and better before but the difference is not exaggerated. There are no miracles.
In my opinion, if I had a KLX250 KLX300 or prior to the year 2007 would prove to set you cams, 2009, I think the use and improves engine performance. But I can assure you. Since then at me if I work best cams 2009.
Visually it is almost imperceptible, but on the bike itself noticeable difference disappears as a dip or bump in the medium rpm.
I checked part numbers for klx300 and klx250 several different years for both and the part numbers for the intake cam is same for all. (12044-1327)
2003 and later klx300 exhaust has a different part number (12044-1487), but a 2000-02 klx300 exhaust has same part number as all klx250's (12044-1365)
Last edited by John65; 06-25-2012 at 03:23 PM.
#370
06-26-2012 | 12:51 AM
Senior Member
Joined: Mar 2009
Posts: 333
From: Quebec, Canada
1st Gear Member
Well, first of all say that I think all the data that specifies Kawasaki, so personally I prefer to check things.
In this picture we are left camshaft klx250EFI of 2009
On the right camshaft for a KLX300 2000. Theoretically it is the same as the 250cc installed until 2007. They were the same reference.
Klx300 cam 33'30mm measured high, while the 2009 measures 33'20mm EFI
But most important is that the EFI cam 2009 has a broader curve, wider. Therefore remain open longer.
In summary, the cam 2009 pushes the valve 0'10mm less, but more time remains open.
I tested the cam KLX300 (2000) in my 2009EFI increased engine capacity to 300cc and power achieved is slightly lower than the standard cam. (Always with the changes made Marcelino complete). The feeling is that the cams 2009 are less steep and allows to have a full engine that drives more and better before but the difference is not exaggerated. There are no miracles.
In my opinion, if I had a KLX250 KLX300 or prior to the year 2007 would prove to set you cams, 2009, I think the use and improves engine performance. But I can assure you. Since then at me if I work best cams 2009.
Visually it is almost imperceptible, but on the bike itself noticeable difference disappears as a dip or bump in the medium rpm.
In this picture we are left camshaft klx250EFI of 2009
On the right camshaft for a KLX300 2000. Theoretically it is the same as the 250cc installed until 2007. They were the same reference.
Klx300 cam 33'30mm measured high, while the 2009 measures 33'20mm EFI
But most important is that the EFI cam 2009 has a broader curve, wider. Therefore remain open longer.
In summary, the cam 2009 pushes the valve 0'10mm less, but more time remains open.
I tested the cam KLX300 (2000) in my 2009EFI increased engine capacity to 300cc and power achieved is slightly lower than the standard cam. (Always with the changes made Marcelino complete). The feeling is that the cams 2009 are less steep and allows to have a full engine that drives more and better before but the difference is not exaggerated. There are no miracles.
In my opinion, if I had a KLX250 KLX300 or prior to the year 2007 would prove to set you cams, 2009, I think the use and improves engine performance. But I can assure you. Since then at me if I work best cams 2009.
Visually it is almost imperceptible, but on the bike itself noticeable difference disappears as a dip or bump in the medium rpm.
I looked at the part numbers too, on RATV, and saw the same part number for exhaust cam (12044-0175), for 2006, 2007 and 2009. There is also an unclear mention about this part replacing 12044-1365. I'm not sure, but it looks like exhaust cam for 06-07 and 09+ are the same, and not exactly like the KLX300.
What is your reference for saying that KLX250 up to 2007 have the same part number as KLX300 for the exhaust cam?