Crf 250/kdx hybrid
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Crf 250/kdx hybrid
Just picked up an 07 crf250 roller and i have a spare 96 kdx 200 motor freshly rebuilt so me thinks a hybrid needs to be done.
Its a twin pipe model and im thinking i will need to reduce the diameter through the pipes? any ideas? Will put some pics up soon as, thanks.
http://s1207.photobucket.com/albums/bb462/cj555rally/
Its a twin pipe model and im thinking i will need to reduce the diameter through the pipes? any ideas? Will put some pics up soon as, thanks.
http://s1207.photobucket.com/albums/bb462/cj555rally/
Last edited by cj555rally on 04:00 pm Apr 02 2012, edited 1 time in total.
- Tedh98
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Re: Crf 250/kdx hybrid
If I'm understanding this correctly, you can't (well I guess you could if you want the engine to run like garbage) use a 4 stroke pipe on a 2 stroke. You'll need to figure out how to make a KDX (or similar) 2 stroke pipe fit.cj555rally wrote:Its a twin pipe model and im thinking i will need to reduce the diameter through the pipes? any ideas?
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Re: Crf 250/kdx hybrid
Guess i didnt explain too good! I mean using the crf silencers. I have a DOMA expansion chamber i can mod to fit but was wondering if i needed to reduce the silencer id as 4 strokes are bigger or just find a couple of 2 t silencers? Just thought it would be different to have twin pipes.Tedh98 wrote:If I'm understanding this correctly, you can't (well I guess you could if you want the engine to run like garbage) use a 4 stroke pipe on a 2 stroke. You'll need to figure out how to make a KDX (or similar) 2 stroke pipe fit.cj555rally wrote:Its a twin pipe model and im thinking i will need to reduce the diameter through the pipes? any ideas?
- Tedh98
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Gotcha.
2 strokes are sensitive to exhaust changes. I'm thinking that anything you do that takes you too far away from the stock based set-up is going to hurt performance more than help.
But if you don't mind spending time and some money trying to make it work, you don't have much else to loose.
I'm not sure if this makes sense, but I'd find out the ID of the KDX silencer and then find tubes 1/2 that diameter for each CRF silencer.
2 strokes are sensitive to exhaust changes. I'm thinking that anything you do that takes you too far away from the stock based set-up is going to hurt performance more than help.
But if you don't mind spending time and some money trying to make it work, you don't have much else to loose.
I'm not sure if this makes sense, but I'd find out the ID of the KDX silencer and then find tubes 1/2 that diameter for each CRF silencer.
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"I'm not sure if this makes sense, but I'd find out the ID of the KDX silencer and then find tubes 1/2 that diameter for each CRF silencer."
To be precise, (not that I think it'll matter much) that won't be the same, check your math, you'll see it doesn't add up
To be precise, (not that I think it'll matter much) that won't be the same, check your math, you'll see it doesn't add up
02 KX 200 hybrid: RB head and carb
Sold ☹ DRZ 400 SM
bike build: http://www.kdxrider.net/forums/viewtopi ... ike+stable
bike profile http://www.kdxrider.net/forums/viewtopi ... 0709#30709
newb info: http://www.kdxrider.net/forums/viewtopi ... 57#p117919
jetting guide: http://www.kdxrider.net/forums/viewtopi ... 105&t=1156
Sold ☹ DRZ 400 SM
bike build: http://www.kdxrider.net/forums/viewtopi ... ike+stable
bike profile http://www.kdxrider.net/forums/viewtopi ... 0709#30709
newb info: http://www.kdxrider.net/forums/viewtopi ... 57#p117919
jetting guide: http://www.kdxrider.net/forums/viewtopi ... 105&t=1156
- Tedh98
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Yeah, there was absolutely no engineering or math behind that recommendation.scheckaet wrote:"I'm not sure if this makes sense, but I'd find out the ID of the KDX silencer and then find tubes 1/2 that diameter for each CRF silencer."
To be precise, (not that I think it'll matter much) that won't be the same, check your math, you'll see it doesn't add up
- scheckaet
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yeah I figured.
(for example) if the kdx id is 40 mm, to get the same surface with 2 pipe you'd need 2 pipe with ID of 28.28 mm.
(for example) if the kdx id is 40 mm, to get the same surface with 2 pipe you'd need 2 pipe with ID of 28.28 mm.
02 KX 200 hybrid: RB head and carb
Sold ☹ DRZ 400 SM
bike build: http://www.kdxrider.net/forums/viewtopi ... ike+stable
bike profile http://www.kdxrider.net/forums/viewtopi ... 0709#30709
newb info: http://www.kdxrider.net/forums/viewtopi ... 57#p117919
jetting guide: http://www.kdxrider.net/forums/viewtopi ... 105&t=1156
Sold ☹ DRZ 400 SM
bike build: http://www.kdxrider.net/forums/viewtopi ... ike+stable
bike profile http://www.kdxrider.net/forums/viewtopi ... 0709#30709
newb info: http://www.kdxrider.net/forums/viewtopi ... 57#p117919
jetting guide: http://www.kdxrider.net/forums/viewtopi ... 105&t=1156
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- diymirage
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i remember ages ago, when i was in my early teens, i used to put around town on small 50CC 2strokers
DTRs, TSXs, MTXs, that sort of things
anywho, there was a local partshop who carried dual exhausts kits for these 50cc bikes and they may or may not have been made by a company called "proma"
(did a quick search and also found a guy with a firebox dual exhaust)
http://www.brommerforum.nl/gallery/view/2139/2/3
DTRs, TSXs, MTXs, that sort of things
anywho, there was a local partshop who carried dual exhausts kits for these 50cc bikes and they may or may not have been made by a company called "proma"
(did a quick search and also found a guy with a firebox dual exhaust)
http://www.brommerforum.nl/gallery/view/2139/2/3
newbbewb wrote:DIYmirage has it right.
-1996 KDX 200 woods weapon (converted to 99 green body)
-1996 KDX 200 plated street toy (barney edition)
-2003 Yamaha TTR125-L (wifeys bike)
-1997 KDX 220 project bike
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Yes you need to concentrate on the major frame mod. The frame Y will need to be cut and relocated higher for clearence of the pipe at the exhaust port exit.cj555rally wrote:Hmmm, maybe the con's out weigh the pro's here. Think i will concentrate on getting the motor and expansion chamber installed then decide on silencer options. Thanks for the input.
- SS109
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Heat treating, or the lack thereof, shouldn't be an issue. Guys over at KXrider have done plenty of KX500af conversions with no heat treating and having no issues.
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Not heard of anyone heat treating after welding and have read a fair few project threads on various forums? When i have welded it all up and done all the other little mods im sure it will need i intend to have the frame and swingarm powder coated. This will involve heating but not to a high enough temp to alter anything i would guess??
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