Big Bore Kits with Finished Block
LTZ400 - KFX400
Available exclusively from Big Bore Thumpers.
Finish bored, nikasiled cylinder. Featuring race-style forged piston from JE. Big bore head and base gaskets. Every kit also includes an APE billet manual cam chain tensioner (as shown on block.)
Kawasaki KFX400 (2003 - 2006)
BKK400
$429.00
Suzuki LTZ400 (2000 - 2009)
BKS400
$429.00
New Fully Assembled Cylinder Heads
TRX450R (2004 - 2009) 
BRAND NEW Honda cylinder head with the ports matched to the seats. APE stainless steel* intake and exhaust valves. High performance valve springs, specialy matched for ultimate valve control. Manufactured from "super clean" chrome silicone wire. Titanium valve spring retainers and steel spring bases.
Ready to bolt on. This is an outright purchase with no core required.
Honda TRX450R (2004 - 2005)
TRX450-4
$575.00 (order this item online!)
Honda TRX450R (2006 - 2009)
TRX450-9
$549.95 (order this item online!)
To purchase this cylinder head fully race-ported, click here.
Manual Cam Chain Tension Adjusters
APE manual cam chain tensioners are designed to replace the automatic and hydraulic tensioners on high performance engines. The automatic adjusters can back out when the throttle is closed suddenly at high rpm. This allows the cams to go momentarily out of time, and can result in bent valves and/or serious engine damage. Hydraulic tensioners have a tendency to put too much tension on the chain guide under high rpm/high oil pressure conditions, resulting in premature wear. Both problems can be eliminated with the installation of the APE manual tensioner.
Click here for a complete listing of manual cam chain tensioners available from Big Bore Thumpers.
