Read these notes before doing anything. There are suggestions listed below with all cams.
   The original 45 & U-Series cams have approximately the same duration on both the intake and exhaust cams. However, for performance use, Harley-Davidson side-valve (flathead) motors need more intake cam duration than exhaust cam duration (the factory race motors used about 30-35° more). This is partially due to the fact that the intake ports are fairly small, badly shaped, and include many inefficient curves, while the exhaust valves are relatively large with much better ports.
   When planning a street motor, or a motor for a heavy bike, a mild intake cam can be used with the stock exhaust cams. As the intake cams get hotter (more duration), the same bias should be retained - use an exhaust cam with less duration (milder than the intake cam). Never install hot exhaust cams with stock intake cams.
   A high performance motor must use hotter intake cams to increase volumetric effiency (torque), and move the power higher up on the RPM scale. These should be used with somewhat milder exhaust cams as mentioned, supra, but this will not work with a restrictive exhaust system. A high backpressure muffler will completely confuse the carburetor and make accurate jetting nearly impossible. These cams only work well with completely open exhaust, or low restriction muffler such as Screaming Eagle, Cycle Shack, SuperTrapp, etc.
   Straight pipes with internal baffles are an extremely bad idea for any motor.
   No motor “needs” backpressure, there is no “minimum backpressure” required to make a motor work. If the motor runs better with more backpressure, the carburetor adjustment was incorrect. What is required is a minimum exhaust gas speed for the motor to operate cleanly, which is why larger diameter exhaust pipes are absolutely not needed.

   The tuned exhaust pulse produced by open pipes will interfere with carburetor operation at certain RPM. This can be reduced inserting a reflective object to “break up” the pulse. This can be done by drilling a ¼” hole 1” from the open end and inserting a 1” long bolt into the pipe secured with washers & nut, and reduce the effect without loss of power. A better shape is the old school “Snuff-or-Not” product. This is no longer available, but one can be made from small hardware parts. Note the spring and adjustment knob for selecting position: with or against the gas flow. Click the image for a larger view.

   45 strokers using 4-7/16” or larger flywheels should use bigger cams than stock stroke engines.    No sidevalve cams require piston to valve clearance. Some will require valve clearance in the head (as noted). All hotter cams work better with heavier valve springs. All hotter cams require minor carburetor adjustment for best results. Linkerts and other carburetors with limited adjustment range may be difficult to tune with hot cams, especially with open exhaust. Mikunis, Amals and other carburetors with multiple circuits are easier to re-jet but will still require substitution of minor components especially to the idle/pilot system.    The re-grinding process re-shapes the original cam lobes. No welding has been needed in the past, because the roller tappet does not require a specially-hardened surface (as flat tappets do), and the new lobe shape can be made from the original with only minor metal removal (mostly from the base circle). This is why these profiles are limited to only slightly more lift than the original lobe.
   The process locates the new lobe center exactly at the existing point of maximum lift. The extra duration is divided equally between both ends of the cam event. For example, an intake cam with 30° extra duration will open the valve 15° sooner and close it 15° later, etc. Alternate lobe centers are not possible.
   For those who wish to get the best results from their cam installation, minor adjustments to the installed position are possible by modifying the motor itself. Click here for more details: .

   Cam specifications listed below (such as “278º/.320”, etc.) give the 1

^st

number as the duration in degrees @ .010” lift, 2

^nd

number as the valve lift in inches. The approximate duration at .010” of the standard 45 cam is 240°, the UL is 260°. The intake lobe center is at approximately 102-103°. The standard 45 lift and lobe height is .312”, UL is .375”, WR or K is .344”, KK/KHK is .375”, KR is .395” or larger. We have no other information about the stock cams.
   These are the ONLY grinds available. Please make your own selection. Generally, if you can’t decide between 2 cams the smaller one is the safer choice. Regrinding can also repair minor lobe damage (same prices).
   Attention: KNS Kustoms is the source of this product, not Victory. Please read the detailed and comprehensive information provided for you on this page, do not e-mail and ask the questions answered below. There is no answer to “Which cam is best for my motor?”.
   Questions: E-Mail KNS Kustoms: . Questions sent to Victory will not be answered..

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   For detailed information about jetting and adjusting the Linkert Model “M” brass carburetor, we suggest “The Linkert Book”, click here for details: , or for the Mikuni “VM” round-slide carburetor “Mikuni Tuning for Harley-Davidsons”, click here for details: .

Harley-Davidson Cams

25505-06R

Intake Cam Set, 45; 278º duration, .318” lift, requires no work to install, great drop-in for stock motors, rough equivalent to factory WLDR cam, works well with stock exhaust cams, mild timing requires only minor carburetor mixture adjustments. Exhaust cam recommendation: 25515-06R . This cam is too mild for a stroker engine.

$135.

25506-06R

Intake Cam Set, 45; 298º/.357”, hot, better top-end power than 25505-06R (above), streetable with high compression, large carburetor & our big valves for major power boost, requires minor (.040” maximum) valve spring & valve pocket clearancing especially with big intake valves, use with 25515-06R exhaust cams.
   This cam is slightly hotter than 25507-06R (below), except for less maximum lift. Heavier valve springs strongly recommended. The slightly lower lift allows smaller chamber volume for maximum compression. Exhaust cam recommendation: 25515-06R .
   This cam is a good choice for a stroker engine.
   Cams can be slightly advanced for best cylinder pressure, which will give more overlap; for experienced engine builders only. Click here for more information on re-timing cams: .
   Warning: Linkerts and other carburetors with limited adjustment range will be somewhat difficult to tune with this cam, especially with open exhaust.

Intake Cam Set, 45; 294º/.377”, hot, best for motors with improved breathing (relieved, ported manifold, big valves) & high compression. Requires minor (.060” maximum) valve spring & valve pocket clearancing especially with big intake valves, should be used with heavy valve springs and 25515-06R exhaust cams. Still streetable!
   This cam is slightly milder than 25506-06R (above), except for more maximum lift. The higher lift requires a bit more room in the chamber, lowering compression slightly.
   Excellent for strokers. Heavier valve springs strongly recommended. Exhaust cam recommendation: 25515-06R .
   Cams can be slightly advanced for best cylinder pressure, which will give more overlap; for experienced engine builders only. Click here for more information on re-timing cams: .
   Warning: Linkerts and other carburetors with limited adjustment range will be somewhat difficult to tune with this cam, especially with open exhaust.

25527-06R

Intake Cam Set, UL; 294º/.377”, requires no work to install, OK as “drop-in” for stock motors, but better with other breathing mods, OK with your stock exhaust cams. Exhaust cam recommendation: 25515-06R .
   Warning: Linkerts and other carburetors with limited adjustment range may be somewhat difficult to tune with this cam, especially with open exhaust.

25528-06R

Intake Cam Set, UL; 314º/.380”, very hot, high RPM use only, requires no work to install, requires high compression and extensive breathing mods, suggested for strokers only. Heavier valve springs strongly recommended.
   Cams can be advanced for best cylinder pressure, which will result in high overlap; for experienced engine builders only. Exhaust cams: 25515-06R . Click here for more information on re-timing cams: .
   Warning: Linkerts and other carburetors with limited adjustment range will be very difficult to tune with this cam, especially with open exhaust.

Exhaust Cam Set, 45; 278º/.318”, requires no work to install, use with 25505-06R, 25506-06R or 25507-06R intake cams (not with stock intake cams).

$120.

Exhaust Cam Set, UL; 294º/.377”, requires no work to install, use with 25527-06R or 25528-06R intake cams (not with stock intake cams).

Indian Cams

Cam-001

Cam set, Chief 74 & 80; 304º/.470”.

$150.

Cam-046

Cam set, Scout; 300º/.518”

Harley-Davidson Side-Valve Cam Profiles

Part Nº

Lift

.010”

.020”

.040”

.050”

.100”

.150”

.200”

.300”

Standard 45 (approximate)

.312”

240°

NA

200°

NA

Standard UL (approximate)

.375”

260°

NA

215°

NA

25505-06R, 25515-06R

.318”

278°

270°

256°

250°

223°

194°

162°

  62°

25507-06R, 25527-06R

.377”

294°

288°

276°

270°

244°

218°

190°

124°

25506-06R

.357”

298°

290°

280°

274°

246°

218°

188°

112°

25528-06R

.380”

314°

310°

300°

294°

268°

242°

210°

136°

To order cams: print this page, fill in your information in the box below, circle the cams you want above, thoroughly clean and dry the cams, then box your own cams, add the correct postage to the price listed, include full payment and ship to KNS Kustoms at the address below.

My name:

My address:

Zip:

My motor is a:      45      UL     Chief      Scout

Cams enclosed for re-grinding:  #1  #2  #3  #4

Amount of payment enclosed:  $

   You cannot purchase these cams outright from us, they must be ground on your own good cams, which must be shipped to us for processing. The accuracy of the new cam profile depends in part on the condition of your own cams and journals (shafts). The grinder rotates the cam on the journal centers. Delivery back to you takes about 6 weeks. It is your own responsibility to see that the cams you send us are in good condition, and are carefully packed to avoid damage in transit. If lost in transit, your claim is against the shipper, not us, so insure for the replacement value (we suggest at least $150. per set for 45, $250. for U-Series, Chief & Scout), and keep your receipt. If necessary, we can verify the value.
   U.S. customers: add $20.00 postage & insurance for a set of 4 cams (2 cams: $15.00). Canadian & Foreign customers: e-mail me for a postage quote before sending cams & payment: . Ship your cams & payment to:

   Your cams will be shipped back to you insured for $300. (each cam = $75., $150. set of 2, etc.). If this is not enough coverage, you MUST let us know when you ship them to us. There will be an additional charge for the extra insurance. If the cams are lost, you can NOT get replacement cams from us, only the insurance coverage.

Cam Identification

   H-D cams are numbered in order of placement in the motor, beginning with #1 at the left (back) side of the cam chest. H-D intake cams are #2 & 3, exhausts are #1 & 4; be sure you send the right ones. Click here for more information on Harley-Davidson cams: . Here they are, as seen from the right side of the motor (with the cam cover removed), with the #1 rear exhaust cam on your left:

Cam Nº

1

2

3

4

Valve

Rear Exhaust

Rear Intake

Front Intake

Front Exhaust

Drive Details

1 gear +
pump drive tangs

2 gears +
ignition drive spiral

1 gear

2 gears

Indian cylinders (front & rear) each have their own cam: you must send both.