wr450f 06 model valve clearance question

wr450f 06 model

650 km's

not ridden overly hard

grey wire

air box

fmf pipe

Never been check for valve clearance

Serviced every 250km (oil, filter)

Hello guys,

I have recently had a mechanic check my valve clearances and these where the results.

Exhaust Valves (pad changed from/to)

1. 170 to 160 (Measured clearance -0.00~0.04)

2. 169 to 160 (Measured clearance -0.00~0.04)

Intake Valves:

1.180 to 175 (Measured clearance -0.15~0.19)

2.185 to 180 (Measured clearance -0.15~0.19)

3.180 to 172 (Measured clearance -0.10~0.14)

My questions:

1.Since the valves have never been done ... is there any reason why the original pad thickness was not 175 as specified in the manual.

2. What could of caused such a small clearance across the board?

3. Is it possible to get pad increments other than by 5 ... eg. 172 and 169?

4. How can i check to see if this mechanic is not talking bulldust?

Also .. he beleives that the needle in the carby is the restricted type and needs to be replaced ..... how can i confirm this? and is there a big performance difference if this is done given the other mods

Cheers.

wr450f 06 model

650 km's

not ridden overly hard

grey wire

air box

fmf pipe

Never been check for valve clearance

Serviced every 250km (oil, filter)

Hello guys,

I have recently had a mechanic check my valve clearances and these where the results.

Exhaust Valves (pad changed from/to)

1. 170 to 160 (Measured clearance -0.00~0.04)

2. 169 to 160 (Measured clearance -0.00~0.04)

Intake Valves:

1.180 to 175 (Measured clearance -0.15~0.19)

2.185 to 180 (Measured clearance -0.15~0.19)

3.180 to 172 (Measured clearance -0.10~0.14)

My questions:

1.Since the valves have never been done ... is there any reason why the original pad thickness was not 175 as specified in the manual.

2. What could of caused such a small clearance across the board?

3. Is it possible to get pad increments other than by 5 ... eg. 172 and 169?

4. How can i check to see if this mechanic is not talking bulldust?

Also .. he beleives that the needle in the carby is the restricted type and needs to be replaced ..... how can i confirm this? and is there a big performance difference if this is done given the other mods

Cheers.

1.The 175 in the manual is just an example. They will all be different. 2.Valves will tighten up as they seat with some break in time. 3.You can buy Honda shims for the crf450 in 2.5 increments. 4.Do the job yourself. If your needle is the stock non adjustable one then yes you could see an improvement with better jetting. :thumbsup:

You've got a pretty good answer from trailordune, see if there are any of the great Aussie contributors in your neck of the "outback" and see if they wouldn't mind helping you out a bit. :cheers: WR Dave.

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