2010 YZ 450 F Interesting info

[Skotten]

This is some stuff I found, everyone most likely knows this stuff but here goes;

1. The lightweight aluminium cylinder features a ceramic composite coating which is applied directly to the aluminium, eliminating the need for a heavy iron sleeve or liner. The ceramic coating insures faster, more uniform heat dissipation, reduced friction and a longer service life.

2. Piston oil cooler utilizes a pinpoint nozzle that directs oil to the desired portion of the cylinder and underside of the piston, which reduces piston, cylinder and rod temperatures for great durability.

3. Centrally located spark plug and the new design of the 4-valve head promotes a "tumbling effect" of the inbound fuel / air for better combustion, improved throttle response and power output.

4. The "reversed" design allows for a straight intake path into the cylinder, providing maximum intake flow and efficiency for excellent power. The front positioned intake means that engine heat will have less "heating effect" on the incoming fuel charge (cooler fuel helps increase power).

5. Lightweight titanium valves (intake & exhaust) and new load-reduced oval valve springs reduce reciprocating mass for less friction, faster-revving and smoother-hitting power delivery across the rev range.

6. The cylinder is "offset" relative to the crankshaft to reduce frictional losses between the piston and the cylinder wall during the power stroke. This offset design is a first on a Yamaha motocross machine.

7. The cylinder is "offset" relative to the crankshaft to reduce frictional losses between the piston and the cylinder wall during the power stroke. This offset design is a first on a Yamaha motocross machine.

8. New, more rigid crankcase to accommodate the increased engine power

9. New design crankcase utilizes an integrated oil tank inside the cases to supply oil to the dry sump lubrication system. This design concentrates mass lower in the frame for optimum handling and lighter weight feeling. There are no exterior oil lines with this design and the internal oil tank is designed to promote air - oil separation.

10. Special cylinder design features cutaways that allow the air "trapped" under the piston to enter a side chamber (or cutaway) to reduce horsepower-robbing "pumping losses."

11. The crankcase also utilizes cutaways to reduce "pumping losses". The crankcase cutaways match the cutaways in the cylinder for maximum efficiency.

12. All new short-skirt, forged piston provides excellent reliability, less mechanical vibration and reduced weight.

13. Newly designed piston rings reduce friction for improved power and reduced oil consumption.

14. Revised, lightweight gear driven balancer shaft reduces vibration for improved rider comfort and less rider fatigue.

15. The crankcase features a tri-axis layout for the crank, main and drive axles. This tri-axis design keeps the crankcase more compact while also centralizing mass for excellent handling. All of the shafts are positioned low in the cases to maintain a low centre of gravity.

16. Revised multi-plate wet clutch features a new clutch push lever assembly and revised push rod. The benefit is improved clutch feel and reduced clutch lever effort.

17. Revised, 5-speed transmission features "involute splines" on the transmission axles to ensure smooth shifting and instant hook-up under power. There are numerous changes to the transmission including engagement dog shape, shift cam "pattern" and revised shift forks. The benefit is smooth, positive shifting.

18. All new Keihin 44mm throttle body fuel injection system is a battery-less design for reduced weight and is designed specifically for MX applications. The 12-hole injector maximizes fuel atomization for more complete combustion and great power output. The benefits of fuel injection include constant ongoing adjustments to insure the optimum fuel - air ratio regardless of outside air temperature and altitude. Other benefits include improved starting and improved throttle response. The system is equipped a throttle position sensor (TPS), plus a range of sensors (engine temp, outside air temp and air pressure etc.). There is also a cold start and fast idle knob which doubles as an idle adjuster too.

[saccityfire]

You sound like a Yamaha sales person.

[grayracer513]

Where did we cut and paste that from?

[1Yamaha1]

This is some stuff I found, everyone most likely knows this stuff but here goes;

5. Lightweight titanium valves (intake & exhaust) and new load-reduced oval valve springs reduce reciprocating mass for less friction, faster-revving and smoother-hitting power delivery across the rev range.

I wonder why Yamaha wanted to reduce reciprocating mass. They spend that money on titanium valves and then people add a FWW to give it more reciprocating mass. Doesnt make sence to me.?

[SparksXR426]

reciprocating mass blah blah piston skirt blah blah blah ?

Will it get me to the top of that hill or not?

[ReedRulz]

reciprocating mass blah blah piston skirt blah blah blah ?

Will it get me to the top of that hill or not?

You may need to read Lance Armstrong's book "It's not about the bike"

[SparksXR426]

You may need to read Lance Armstrong's book "It's not about the bike"

But, buddy at the dealership said that once I purchased this fancy new maa-cheene with its fancy new things I'd be pullin all the holeshots and winnin all the races! ?

[DBMX 925]

But, buddy at the dealership said that once I purchased this fancy new maa-cheene with its fancy new things I'd be pullin all the holeshots and winnin all the races! ?

Believe the hype!

[jratcliffe3]

I wonder why Yamaha wanted to reduce reciprocating mass. They spend that money on titanium valves and then people add a FWW to give it more reciprocating mass. Doesnt make sence to me.?

Reciprocating mass = mass that moves up and down (pistons, valves)

Rotating mass = mass that spins around (crank, flywheel, geard, clutch etc)

A FWW is rotating mass, not reciprocating

[grayracer513]

Precisely.

Less reciprocating mass attached to the crank makes the engine easier to balance, also.

[ReedRulz]

Precisely.

Less reciprocating mass attached to the crank makes the engine easier to balance, also.

I had a new crank, rod, piston and cylinder installed on my 2007 YZ450F. Should I have had it balanced? It seems like it vibrates more now then before

[grayracer513]

I had a new crank, rod, piston and cylinder installed on my 2007 YZ450F. Should I have had it balanced? It seems like it vibrates more now then before

If they were OEM replacement parts, it usually isn't necessary to balance. Aftermarket parts are another matter.

[ReedRulz]

If they were OEM replacement parts, it usually isn't necessary to balance. Aftermarket parts are another matter.

The crank and rod are Hot Rod and the piston is JE.

[husqy360]

The crank and rod are Hot Rod and the piston is JE.

so its yes id guess.

[grayracer513]

Hot Rods cranks are an overall good quality, but they are notorious for not being well balanced even for the sock piston weight. If the JE piston weighed a significantly different amount that the OEM, then it would also have made it necessary to balance all by itself.

[ReedRulz]

Hot Rods cranks are an overall good quality, but they are notorious for not being well balanced even for the sock piston weight. If the JE piston weighed a significantly different amount that the OEM, then it would also have made it necessary to balance all by itself.

Could being unbalanced be damaging to the motor or is it more for comfort of not having the vibration?

[grayracer513]

Severe vibration fatigues things, so they aren't good in any sense, but in a well balanced single with a counter balance shaft, imbalances exist, but in opposition to each other, so that they cancel each other. The forces that would produce a vibration still exist within the individual rotating assemblies, and so does the load they produce, but they cancel out within the whole assembly so that you don't feel them.

By and large, severe vibrations are probably harder on the attached components and the rider than on the engine itself.

[SkyHarborCowboy]

Ride a 2 Stroke 500 and you will find out what vibrations are!

LOL!

[SkyHarborCowboy]

Ride a 2 Stroke 500 and you will find out what vibrations are!

LOL!

I wish to God I could put a counter balancer on my CR500R! Actually, any 2 Stroke for that matter. My 450 is like a sewing machine compared to the smokers!

Joe

[Skotten]

Where did we cut and paste that from?

I dont remember gray Just thought it was interesting info...