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cannondale27
11-06-2003, 06:07 AM
Do any of you guys know what system is used on the CRF dirtbike to limit engine braking when you let up on the gas?I have heard it is a sprag clutch.Is this same system on the new 450 quad?Have any of you ridden a crf450 powered custom quad with this system?What did you think of it in the corners(engine braking)?Thanks.
ATC83
11-06-2003, 06:49 AM
I'm not sure what a sprag clutch is but the 450 engine was specifically sedigned to have as little engine braking as possible. Depite what the factories say, they always claim that it was designed this way to go faster on the trake which is partially true, this was done to help with the transition from a 2-stroke motocross bike (no engine braking) to a 4-stroke motocross bike. Its all about money, the factories no that the EPA has given the 2-stroke the death sentence. Weather we like it or not the 4-stroke is the future. The only way I know to gain or reduce engine braking is to add or reduce flywheel weights. Where are you from in Wisconsin and where do you ride?
cannondale27
11-06-2003, 03:10 PM
I am between Milwaukee and greenbay right on I-43 Manitowoc.I do alot of racing and when I trailride Oconto,Dunbar,Black River Falls.
A sprag clutch is a one way clutch like the clutch that is used with a electric start.Does anyone know where a online manual is for the CRF450 motor?
A buddy of mine built a CRF quad and he had to relearn how to corner with it since he wasnt used to having to brake as hard as other 4st's before the corners.Once he got used to it it seemed as though he was faster.Lack of engine braking forced him to carry more speed into corners.Just something to get used too.
Guy400
11-06-2003, 07:24 PM
It's not a manual but it's as close as I could get:
http://www.servicehonda.com/hard%20parts/off%20road/crf450r%2004/crf450r_04%20frames%20page.htm
cannondale27
11-06-2003, 10:39 PM
Hey thanks guy 400!
I cant seem to find any sprag clutch in there.I wonder how they limited the engine braking?
Guy400
11-07-2003, 04:27 AM
This is just a guess with nothing to base it on but maybe they use the auto-decompressor for kickstarting as a way to blow off cylinder pressure during decel.
ATC83
11-07-2003, 07:22 AM
Originally posted by cannondale27
I am between Milwaukee and greenbay right on I-43 Manitowoc.I do alot of racing and when I trailride Oconto,Dunbar,Black River Falls.
A sprag clutch is a one way clutch like the clutch that is used with a electric start.Does anyone know where a online manual is for the CRF450 motor?
A buddy of mine built a CRF quad and he had to relearn how to corner with it since he wasnt used to having to brake as hard as other 4st's before the corners.Once he got used to it it seemed as though he was faster.Lack of engine braking forced him to carry more speed into corners.Just something to get used too.

I’ve been to Oconomowoc a couple of times. I got my undergraduate and graduate degree from UWM. I really like eastern Wisconsin. I have some friends that live in Menomonee Falls. Have you ever been to the Derecuse Motocross Park (I’m not sure I spelled that right)? I hear it a cool place to ride. We are planning a trip to Milwaukee in the spring and I was thinking about stopping on the way down. If you are every up this way let me know and I can show you some cool places to ride up here. What kind of Cannondale are you riding?
RobRacing
11-07-2003, 09:56 AM
I have also heard that the auto-compresion realse is how the limit engine braking.
honda350r
11-11-2003, 10:09 PM
The YFZ has horrible engine braking! I have never rode anything that beats you up like the YFZ does!! I hope the Honda is much better!
rtyfz450
11-12-2003, 09:53 AM
I have also heard about the auto-decompressor blowing off cylinder pressure during decel. I know what a sprag clutch is don't think it is anywhere on the 450.

350r,
yfz has hardly any engine braking, I went down a step hill for the first time and I had to lock the brakes because I was accustomed to riding my 440ex. the 400ex has a lot of engine braking by the way, why did you even say that it is not even on the topic, oh wait you know more than everyone so it must be right. It should say you think you know more than everyone.:blah:
honda350r
11-12-2003, 10:18 AM
I think the YFZ has horrible engine braking! I hope the Honda is better! I can comment on any thread I PLEASE!!!!
rtyfz450
11-12-2003, 10:22 AM
lol, ok comment away know it all
BTW nice retraction of your previous statement, you should of left it there if you really think that
89'350RX
11-13-2003, 05:28 AM
Originally posted by ATC83
I’ve been to Oconomowoc a couple of times. I got my undergraduate and graduate degree from UWM. I really like eastern Wisconsin. I have some friends that live in Menomonee Falls. Have you ever been to the Derecuse Motocross Park (I’m not sure I spelled that right)? I hear it a cool place to ride. We are planning a trip to Milwaukee in the spring and I was thinking about stopping on the way down. If you are every up this way let me know and I can show you some cool places to ride up here. What kind of Cannondale are you riding?


I ride Dyracuse a few times a year. They have a nice tight trail that runs through the woods. They also have a killer sand track for MX and ATV's. The track can be tough to ride if it is rutted up from the bikers but overall it is a challenging track with hills, jumps, everything.

Dyracuse (http://www.rapidangels.com/dyracuse.htm)
ATC83
11-13-2003, 06:07 AM
Originally posted by 89'350RX
I ride Dyracuse a few times a year. They have a nice tight trail that runs through the woods. They also have a killer sand track for MX and ATV's. The track can be tough to ride if it is rutted up from the bikers but overall it is a challenging track with hills, jumps, everything.

Dyracuse (http://www.rapidangels.com/dyracuse.htm)

Thanks for the info, I might have to stop in there next spring and take a ride. I love sand tracks.
Pappy
11-13-2003, 06:18 AM
Originally posted by rtyfz450
lol, ok comment away know it all
BTW nice retraction of your previous statement, you should of left it there if you really think that

i took the word from his post as its not wanted on the site.

once again id suggest learning to get along with others on this site instead of trying to bash or flame non stop. you get what you give here.....like it or not.

consider this your first warning...anymore BS from you and your history
honda350r
11-13-2003, 08:18 AM
Originally posted by Pappy
i took the word from his post as its not wanted on the site.

once again id suggest learning to get along with others on this site instead of trying to bash or flame non stop. you get what you give here.....like it or not.

consider this your first warning...anymore BS from you and your history

Thanks Pappy !!
rtyfz450
11-13-2003, 08:28 AM
sorry for insulting you 350r but I have a question, why do you think it rides horrible? It is the same engine as the yz and as we all know it doesn't have that much engine breaking. I have not experienced it, mabe you are just not used to riding a four stroke? trust me the 400ex has about 20x the engine breaking.
honda350r
11-13-2003, 01:08 PM
I have mostly owned 250rs amost 20 of them. I have owned a coulple 400exs. I guess I mostly notice the braking when doing a wheelie and letting off the throttle only to have the front end slam down so hard it hurts my wrist! I do not like the forward feeling of a YFZ !

I may be confusing feeling like going over the bars with enging braking? Either way I feel like the YFZ will ditch me at any moment!

I have rode many new YFZs and done the cam mod on 5 different ones and currently putting a new 13:1 piston head work and cams in my buddies YFZ . I love the motor and can't believe how fast they are! I just hate riding them because they beat me up bad !! My 250rs never beat me up and I ride alot! I do ride only in sand !!