ALL MOTORCYCLES AND ATV's:

1.  Use a high quality motorcycle oil and change it often (about every 20 hours for the average rider, after every race for performance engines).  Lack of quality lubrication will ruin an engine, fast!  Four strokes with replaceable/cleanable oil filters need to have these maintained also.  Powroll has found that only MOTORCYCLE oils (Hondaline, Yamalube, Torco, Powroll brand, etc.) are able to withstand the pounding a clutch and tranny deliver.  Powroll does not recommend Synthetic oils for most four stroke applications (they're fine for two strokes).

2.  Clean and oil your air filter regularly.  Powroll recommends foam filters for the average rider.  Paper filters may offer better airflow, but allow more particulate to reach the engine.  Do not over-oil your air filter.  Follow the directions included on the foam filter oil for proper use.

3.  If you have a new bike, make sure to check every nut and bolt.  Also check spokes.  Use a torque wrench and follow manufacturers specifications.  Older bikes should also have these things checked at least once a year (much more frequently for race bikes).

4.  Use the grease zerks!  If the bike doesn't have grease fittings, at least make sure to lube the axle and swingarm area.  Powroll recommends doing this on new bikes/ATV's also.

5.  Lube the clutch and brake cables.  If you don't have one, purchase a cable luber.  It's the best $10 you'll spend!

6.  Clean your bike.  During cleaning you may see problems which weren't evident when the bike was dirty.

7.  Use the correct heat range plug and change it every 3 months (for a regular plug) or 6 months (for a platinum plug).  Powroll does not recommend split-style plugs.

8.  Use premium pump fuel.

MODIFIED 4-STROKE BIKES & ATV'S -

All of the above, plus:

1.  Proper gearing is the key.  Larger displacement engines will need to go up at least one tooth on the countershaft sprocket, and maybe down a couple in the rear.

2.  Oil.  A good quality motorcycle oil is even more important after the engine is modified.  Synthetic oils are absolutely not recommended in air-cooled four strokes with bigger cams.  Change oil on modified engines even more frequently than their stock counterparts.

3.  After increasing horsepower more than 20% on an engine, you should consider using stronger clutch springs.

4.  Make sure the engine is properly jetted.  Follow the instructions included with your performance parts to ensure correct jetting (or check our Jetting Specs page).  It is not easy to hear when a four stroke is running lean, and a lean condition will damage a four stroke just as easily as a two stroke.

5.  Larger displacement engines may also require different filtration, a different camshaft, and/or bigger headpipe.  Check with the company you are purchasing the bore kit/stroker from for what else may be required.  Failure to match the intake/exhaust sizes with a large displacement engine can cause overheating/seizure problems.

6.  Did we mention oil?  It's really THAT important!  Don't ever cheap out on oil for a performance four stroke.  Even if you save $5 on each quart by purchasing a lesser brand, you'd better invest that money in the lottery and hope for a big win to cover the rebuild costs of a thrashed engine!

7.  Any modified engine will require more care than a stock one.  Be prepared to spend a little more time wrenching between rides.  Areas to be concerned with (other than oil and filters) are valve adjustment, cam chain adjustment (if it's not automatic), and clutch adjustment.  Also pay more attention to the drive chain and sprockets.

8.  Don't ignore funny/new engine noises.  Big bore pistons (especially with a lesser expensive - heavy - piston!) can cause your rod assembly to wear more quickly.  Rod knock is the engine's way of telling you to get in there and do something.  

9.  When installing an extremely large piston (more than 5mm increase on any bore that's 66mm or larger), Powroll recommends a heavy duty rod (check out our 400EX Tough Rod Stroker,  Carrillo or Falicon).  Also, consider increasing bore AND stroke to obtain big displacement instead of just bore alone.  Keeping the engine more square will typically offer better power and reliability.