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Is engine braking bad for lubrication?


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I ride trails and there are a lot of hills... sometimes it is riding down for 2-3 minutes at a time in gear with no throttle input, allowing the engine to slow the rear wheels.

 

With the carbs closed there is not much fuel coming through, but the engine RPM is elevated above idle from gravity rolling the bike down the hill so is there anything to worry about in this case since the engine lubrication comes from the fuel?

 

I wasn't sure if a lower or higher gear would be better or worse, or if the clutch should be pulled and held the entire time or the trans taken out of gear and just let it idle or if it matters at all. :shrugani:

 

 

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There was a kid on here said he would coast down hill with his clutch in an it super heated tranny wasn't getting proper lubrication he said he had pics also looked like gears got real hot

 

 

Sent from my iPhone using Tapatalk

 

This does't even make sense. The tranny is in a bath of oil, not 2-stroke mix. I PROMISE his tranny saw more force and abuse from being IN the throttle than OUT.

Sounds like he let his fluid go too long between changes.

 

 

Also….when you are coasting down a hill with the motor backloaded, the motor is still running, so you are getting fuel and oil into the motor. Hell I know people who forgot to mix oil in the fuel, but since they ran a quality oil normally…the motor survived.

So backloading for a little while is nothing. (Unless your pilot and airscrews are tuned for shit……which is common.)

Edited by WINDYCITYJOHN400
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Thanks for the replies!

I ride at Wayne National Forest in Ohio, some trails head down into valleys and cut back and forth so you're heading down for a longer time than if you just went straight down.

It's technically considered the Appalachian Plateau, part of the Appalachian Mountain range, but just on the edge of it.

 

 

I do blip the throttle on occasion and 3 minutes may not be accurate, but 120 seconds or 2 minutes does, at least it seems like it in some places.

It is also rocky and rutted in places, so sometimes I am using brakes but then sections are smoother and faster and I'm not riding the brakes the entire way down, but I do use them to reel things in sometimes.

 

I also ride them a lot, so it isn't just once this happens, we ride up and down the ridges and valleys on the trail system so I'm either hammering up hills or creeping down them.

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I cant stand engine breaking on a 2-stroke, I dont know why but to me its like raking fingernails on a chalkboard

Well don't ever ride with me. I go 6th to 3rd and motor break all day all over the place.

Main reason why I can't/don't want an over ride.

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I cant stand engine breaking on a 2-stroke, I dont know why but to me its like raking fingernails on a chalkboard

Really? I love engine braking on flat track. I ride much faster times that way, but it requires a bit more compression to work the way I like. I am trying a lower compression this season for reliability, so it may require a different style of riding.
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Usually the air fuel ratio goes rich when you engine break. With  the throttle closed and the rpm's high you get a stronger vacuum though / behind the carbs. So with the stronger vacuum it pulls more fuel through the pilot circuits. 

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