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yep, don't forget your unobtainium valvetrain for stage 2 cams. The valvetrain alone cost me over 1000....used, and i still ahve no stage 2 cams.

Stage 1 cams maybe be available for all soon too. i'm working on that one, and would be more logical for most guys.
 
I was thinking about having my valve train parts copied
You should, maybe i should do the same. do you have cams too? Would be cool to do it through the same company so guys wanting stage 2 can buy a whole kit. Valvetrain and cams.

What Valvetrain do you have? the HRC or Moriwaki? i have the HRC one. i foget what company it is, but i had titanium retainers made to HRC spec for my valvetrain....it was expensive. i think i bought 24 to have spares and it cost me 600.:eek:
 
rare find. there is one for sale though. Problem is you need the ECU/CDI, harness, and tuner box to make it work right. These TB's were not designed for our bikes, they were designed for works bikes which have nothing in common with ours. The heads ont he works bikes were very different then ours.
 
You should, maybe i should do the same. do you have cams too? Would be cool to do it through the same company so guys wanting stage 2 can buy a whole kit. Valvetrain and cams.

What Valvetrain do you have? the HRC or Moriwaki? i have the HRC one. i foget what company it is, but i had titanium retainers made to HRC spec for my valvetrain....it was expensive. i think i bought 24 to have spares and it cost me 600.:eek:
It's Kibblewhite Precision Machining that made the titanium retainers.
Slightly heavier, but far more durable than the aluminum Moriwaki or HRC retainers.
 
1)​

There is a member on speedzilla that I have been in contact with that has some that I plan on picking up
Mori / Kent stage 2
billet cams. Adjustable cam gears. Springs, seats retainers.
12,4mm intake lift and 11,9 exhaust lift ( oem 10.5mm lift in and ex )
Timing:
105° in
107° ex
Sorry if this is a silly question, but i am confused a bit.

According to the manual, stock cams lifts the valves at 1mm height.
That means that the lobe has a 1mm lifted nose from it's circular circumference.

Image


If a staged cam adds 10 or 11mm height on the valve lift, isn't that "too much" for the stock pistons to heads clearance?

2)​

These are not the ones talked about on Speedzilla or the RC forums.
I know the person that has the masters for the HRC cams.
They will be in three configurations.
They are:
.420 lift 258 deg duration @ .04 lift
.470 lift 274 deg duration @ .04 lift
.495 lift 282 deg duration @ .04 lift

There is the posibility of doing another option of .47 lift and 258 deg duration

All but the .420 lift will require springs and retainers.
Are these measurements in inches? I am asking that cause 1mm = 0.03937 in
Something I don't get right, maybe?
 
You should, maybe i should do the same. do you have cams too? Would be cool to do it through the same company so guys wanting stage 2 can buy a whole kit. Valvetrain and cams.

What Valvetrain do you have? the HRC or Moriwaki? i have the HRC one. i foget what company it is, but i had titanium retainers made to HRC spec for my valvetrain....it was expensive. i think i bought 24 to have spares and it cost me 600.:eek:
I have the Roger Ditchfield cams which were made for him by Kent Cams.
 
1)​



Sorry if this is a silly question, but i am confused a bit.

According to the manual, stock cams lifts the valves at 1mm height.
That means that the lobe has a 1mm lifted nose from it's circular circumference.

Image


If a staged cam adds 10 or 11mm height on the valve lift, isn't that "too much" for the stock pistons to heads clearance?

2)​



Are these measurements in inches? I am asking that cause 1mm = 0.03937 in
Something I don't get right, maybe?
On your screen cap, the intake valve will have 1mm lift with the piston at 20 deg BTDC.
At 50 deg ABDC, the intake valve will have 1mm lift.
For a total intake duration of 270 deg.

The exhaust valve will have 1mm lift starting at 50 BBDC, and at 20 deg ATDC.
And will have 1mm lift at 20 ATDC, also for a duration of 270 deg.

With the intake closing at 50 deg ABDC and exhaust opening at 50 BBDC, the intake/exhaust overlap is 100 deg.

For second portion, values are in inches.
.420" = 10.668mm
.470" = 11.938mm
.495" = 12.573mm

.04"= 1.01mm
 
On your screen cap, the intake valve will have 1mm lift with the piston at 20 deg BTDC.
At 50 deg ABDC, the intake valve will have 1mm lift.
For a total intake duration of 270 deg.

The exhaust valve will have 1mm lift starting at 50 BBDC, and at 20 deg ATDC.
And will have 1mm lift at 20 ATDC, also for a duration of 270 deg.
Sorry but I think I don't get something right.
The exhaust valve opens 50 deg BBDC and closes 20 deg ATDC.
That means
20+180+50= 250 deg.
Same thing with the intake valve.
What I see though is that the intake valve opens 20 deg BTDC while the exhaust valve is already open. Exhaust valve closes 20 deg ATDC.
That makes us 20+20= 40 deg overlap.

Image


What am i doing wrong and can't find the same numbers as you did?

With the intake closing at 50 deg ABDC and exhaust opening at 50 BBDC, the intake/exhaust overlap is 100 deg.

For second portion, values are in inches.
.420" = 10.668mm
.470" = 11.938mm
.495" = 12.573mm

.04"= 1.01mm
Thanks Sub....
Image
 
Cams cams cams

Guys I'll cut this short.

I'm trying to search the ends of the earth to find cams for my SP2 or SP1.

I have a WSB Spec top end and only thing missing are the came.
I missed out on the last Mori cams and heads and missed out on the last set of available Kent Cams by 2 secs on eBay.

Keen to look for some cams to find the missing piece to my puzzle and am hoping someone has some ideas or can help.

Cheers
Popes
 
Sorry but I think I don't get something right.
The exhaust valve opens 50 deg BBDC and closes 20 deg ATDC.
That means
20+180+50= 250 deg.
Same thing with the intake valve.
What I see though is that the intake valve opens 20 deg BTDC while the exhaust valve is already open. Exhaust valve closes 20 deg ATDC.
That makes us 20+20= 40 deg overlap.

Image


What am i doing wrong and can't find the same numbers as you did?



Thanks Sub....
Image
Your overlap values are correct.
I was looking at the came timing differently and calculated wrong.
40 deg overlap is actually a bit mild.

In automotive engines, I noticed the following reference:
Trucks, good mileage and torque: 10-35 degs overlap
Daily driven, low rpm performance: 30-55 degs overlap (RC51 40 deg overlap)
Hot street performance: 50-75 degs overlap
Bracket/oval track racing: 70-95 degs overlap
dragster/comp eliminator engines 90-115 degs overlap
 
Your overlap values are correct.
I was looking at the came timing differently and calculated wrong.
40 deg overlap is actually a bit mild.

In automotive engines, I noticed the following reference:
Trucks, good mileage and torque: 10-35 degs overlap
Daily driven, low rpm performance: 30-55 degs overlap (RC51 40 deg overlap)
Hot street performance: 50-75 degs overlap
Bracket/oval track racing: 70-95 degs overlap
dragster/comp eliminator engines 90-115 degs overlap
It all depends on two main factors when deciding of the cams characteristics
1) The rpm range the engine is made to deliver it's maximum power output
2) Valves' lift and diameter

The higher the rpm the engine performs, the longer the overlap duration for optimal chamber "breathing" and maximum mixture intake velocity. But that makes the engine weak on lower rpm so it cannot be used on a commuter bike that rarely redlines.

Valve's lift is the second parameter that dictates the quantity and speed of the intaking mixture. The smaller the lift, the longer it should stay open for the same outcome. The same applies on the valves' diameter

Diesel fuel has different characteristics due to it's way of burning in the cylinder. That's why the diesel engines cannot rev as high as the gas fuel engines. So the cam designs on such engines are totally different on designing point of view.
 
yup. hes about to start on mine
My second build by Roger....If you aren't going to do the startup/tuning, I'd demand to be in the shop in person, videotaping every second...Don't let a dumbass, like John Ethel, explode your new engine by ignoring the low oil pressure warning light!

GL speedster
 

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