Valve Guides            $16.00 per seat plus $5.00  shipping for multiple items please call for shipping prices

stainless steel allen screw kit for left side engine case and sprocket cover  18.95  plus $5.00shipping

SHIPPING CHARGES are based on shipping within the 48 contiguous states in the  United States. I will send you an email if you are outside the 48 contiguous states with shipping charges options. Also, please email me if ordering several parts as I will adjust your shipping charges.  SHIPPING CHARGES are NOT refundable. 

Right side

​$17.95 plus $5.00 shipping

Left side

​$17.95 plus $5.00 shipping

  Stainless Steel Engine Cover Bolts

Heavy Duty Studs - 4

same size as original studs length 7 5/16 inch 

$90.00 plus $5.00 shipping

Replace your studs with a better made, better material, higher torque ability, less stretch which helps to prevent fewer head gasket problems

If you need a part or service not shown, please do not hesitate to give me a call. I have 40 years invested in the Honda motorcycle racing scene and Honda XL350 engine building. Thru these years I have gained a tremendous knowledge about the engines, parts and how to service and build these special motorcycles. I have 10 years of Honda motorcycle dealership experience, as both a service technician and service manager from 1970 to 1979, so I have first hand knowledge about the Honda XL350

Also, contact me if you have used engines or parts for sale.

​Hondajohn 50

ALL ​Base Gaskets

$15.00 plus $5.00 shipping

89.5 mm Head gasket

89 mm Head gasket

86 mm Head gasket

81 mm Head gasket


Heavy duty cam chain- worn chains are likely to break causing  severe engine damage so replace your chain regularly to prevent undue expense and repair

​$85.00 plus $5.00 shipping

ALL ​Head Gaskets 

$35.00 plus $5.00 shipping

Left Cover Gasket - Magneto side

$15.00 plus $5.00 shipping

Right Cover Gasket - Clutch side

​$15.00 plus $5.00 shipping

Base Gasket- .012 thick

Base Gasket- .020 thick

Base Gasket- .031 thick

Gaskets seal the compression in





Forged Custom piston
made in the USA

$225.00 plus $15.00  shipping

2 or 3 ring, pin, circlips

​forged means a stronger more durable piston, higher compression, with superior quality rings equals less ring wear

Heavy Duty Studs - 4

replacement for original studs required when installing cylinder spacer plate length 7 9/16 inch diameter .392

$90.00 plus $5.00 shipping

HBS-250 replacement R & D valve springs.

$140.00 plus $5.00 shipping


​Aligned boring of a damaged cylinder head is needed to use needle bearing cams. Must send head,cover and 4 bolts. Extra charge to remove studs. Extra charge for welding to repair extensively damages cylinder heads.

Nickel bronze valve guides use ​4-5 percent nickel content produces superior resistance to wear, and the approximately 80 percent copper delivers outstanding heat conductivity

      Valve seats            $25.00 per seat plus $5.00  shipping for multiple items please call for shipping prices

stainless steel valves


various sizes and types available please call John for pricing


Valve Springs

Barnett Clutch Springs

Valve springs with aluminum tops

​$185.00 plus $5.00 shipping

Cam Number        Valve  Duration   Lobe     Description and application                                 Intake open/close      running

                               Lift      at .040'    Center                                                                              Exhaust open/close   clearance

127-00 127-00NB  .345"   241'       100.5'    OK with stock pistons and springs. Increased                  20btc/41abc       .003"

                              .310"   243'        103.5'     mid-range, improved torque on and off-road cam.           45bbc/18atc        .003"

127-20 127-20NB  .356"   250'        103'       Best all around on and off-road cam. OK with stock        22btc/45abc       .003"                                  .332"   252'        104'       XL-350 piston. Must check clearance in XL-250.             50bbc/22atc       .003"                                                                         Great mid- range and top-end. Use HVS-250 valve springs.                               

127-40 127-40NB  .365"   243'        103.5'    Use with motified piston and springs.                               18btc/45abc       .004"

                               .365"   243'        103.5'    Best cam for TT, moto-X. Great throttle response           45bbc/18atc      .004"

127-60 127-60NB  .417"   250'        101'       1/8 and 1/4 mile modified midget profile. Strongest          24btc/45abc       .004"

                              .374"   250'         101'      mid to upper range cam. Must use racing piston              46bbc/24alc       .004"

                                                                      and springs. Smooth power band.                                                                      

127-90 127-90NB  .415"    276'        105'      Full race cam. Maximum top-end power. For high           33btc/63abc       .005"

                              .405"    273'        103.5'    R.P.M. applications. 3/8 and 1/2 mile. Must use              60bbc/33atc       .005"

                                                                       #229-H, and racing piston. Must grind cyclinder head

                                                                       for clearance.




$245.00- $575.00

plus $15.00 shipping

​Call John for prices and ordering information


Cylinder Spacer Plate

        quantity 1               

  $90.00 plus $5.00 shipping

Barnett Clutch Springs

aluminum  spacer plate is necessary for long rod stroker crankshaft 5/16 (8mm)

you must use longer studs sold below 7 9/16 inch

1974-1978 Honda XL350 Barnett Clutch 7- kevlar friction plates which are lighter weight, better vibration damping, increase strength and do not heat up like conventional plate material. A good set of clutch plates and springs are necessary in increased horsepower engines.

​OEM# 301-48-1001

1974-1978 Honda XL350 Barnett Clutch Springs Kit

Quantity- 4 springs

OEM # 501-56-04015

​Springs are pre-set, shot-peened and heat treated

​for performance and durablity. A quality set of springs fight fatique, apply better pressure to plates to prevent slipage which transfers better power to the rear wheel.

Barnett Clutch  Springs

​          quantity 4 springs               $39.95 plus $5.00 shipping

Barnett Clutch Springs

Barnett Clutch Plates

​quantity 7 friction plates

​$99.00 Clutch plates only plus $5.00 shipping

       BEST VALUE -$119.95 Clutch Plates and   springs plus $10.00 shipping