g'day guys- i just read the article on this forum on valvetrains- i can't remember the exact wording but if i remember correctly it states that riding conditions that lead to engine over-revving and consequent valve floating in modern 4 strokes (i.e fast revving 4s) include downshifting and engine breaking into corners- i am thinking about buying a WR250F but my riding style is such that i use engine breaking extensively, especially when coming into corners a bit hot. Is this considered bad technique? more so on modern 4ts? what's the story?
downshifting=valve floating?
- Thread starter rowand
- Start date
jmics19067
LIFETIME SPONSOR
- Jan 22, 2002
- 2,097
- 0
as long as your not over speeding the engine. if the engine was designed to run up too say 10,000 rpm as long as everything is fine the valve train won't float tilll you exceed 10,000 rpm . hypothetically if in 4thgear at say 5,000 rpm and you down shift to 2nd and it brings engine speed up to 8,000 rpm you shouldn't have any valve float but if tapped out in 5th and you drop into 1st that is a different story. the main thing is the how high the rpm,s get when you downshift. since I really don,t know the rpm ceiling of the WR and /or your particular riding style /rpms you are hitting I cant say whether it is ok or not.
personally I don't think that engine braking causes any more wear than on the gas except for maybe the back side of the knobbies. If you are beating the snot out of it on the upside or the downside you're still beating the snot out of it is my opinion
personally I don't think that engine braking causes any more wear than on the gas except for maybe the back side of the knobbies. If you are beating the snot out of it on the upside or the downside you're still beating the snot out of it is my opinion
Ol'89r
LIFETIME SPONSOR
- Jan 27, 2000
- 6,958
- 45
Rowand.
With my riding style, I use a lot of engine braking. Never had any problems with my WR 400 or my CRF450 overreving as long as you do it in conjugation with the rear brake.
One thing to watch out for is landing off of a jump. Avoid downshifting in the air and landing in a lower gear with the clutch out. Doing this can cause the engine to overrev.
Just my $ .02
With my riding style, I use a lot of engine braking. Never had any problems with my WR 400 or my CRF450 overreving as long as you do it in conjugation with the rear brake.
One thing to watch out for is landing off of a jump. Avoid downshifting in the air and landing in a lower gear with the clutch out. Doing this can cause the engine to overrev.
Just my $ .02
Similar Topics
-
- Sticky
- Article
