The CRF250L Owners thread

[taninthai]

Originally Posted by Ed@Ford

It's probably a chain length thing

I have just fitted a 43t sprocket to mine still have the 14t on front,however my bike is 6 months old and has 3500 km on it so the chain was a bit stretched and it just fitted on, if your bike is new i dont think a 43t will fit unless you change the front first

[swimmer]

Originally Posted by Guerillah

I woke up to a beautiful sunny day in Southern Arizona (currently 70ºF) so I decided to gas up the bike and take her out on a trail i've never been on before. The trail goes around a small mountain range called the Tortolita's in Tucson, AZ. The complete trail was 40 miles, mostly 2 track. Overall it was pretty easy minus some very deep sand in the washes and one hill climb with lot of large boulders exposed with ruts mixed with large rocks, knocked me off balance, whoops! The rear suspension could definitely be stiffened up, perhaps someone will make a stiffer spring for the budget minded. After the loop I calculated my MPG and it came out to 46 MPG. This is with the following mods: 13T front sprocket, FMF programmer, FMF Q4 muffler, FMF megabomb header. This includes a good amount of wide open throttle so this is about what I would expect to always get with this combination. Some pic..

Nice pictures.

[EEKAMOUSE]

Originally Posted by ramz

At first, there were no sprockets available. Then some of us found 13T front sprockets. Later, 42T rear sprockets became available. And now, there are 43T rear sprockets available. And maybe even larger.

Some history with pics:
http://rickramsey.net/CRF250Lmods.htm#gearing

We have a 13-48 combo on one right now it is nice you guys need to quit messin around and go big haha

[Rjatr]

Originally Posted by taninthai

I have just fitted a 43t sprocket to mine still have the 14t on front,however my bike is 6 months old and has 3500 km on it so the chain was a bit stretched and it just fitted on, if your bike is new i dont think a 43t will fit unless you change the front first

Thanks for the info, probably fit the bigger rear sprocket later.



IT175H
KTM500MX
DT125LC
GPZ500s
CBR900RRT
CBR900RRY
CRF250L

[Bake]

The Bill Blue 280 big bore engine was up and running today. He said he completed the design for the second size engine. Bill's contacts in the business go pretty deep, if he pulls the trigger on these 2 big bore kits, it will happen relatively quickly. It's still his secret what size the bigger engine is, but I think it's about 320cc.
I got my Dobeck fuel controller today and will install it on my bike this weekend. Bill should have the new exhaust tips done soon. I will be testing one of those while he breaks in the 280. He says the cooling capacity can handle a 350, but there just isn't room to go that big.

[taninthai]

Originally Posted by EEKAMOUSE

We have a 13-48 combo on one right now it is nice you guys need to quit messin around and go big haha

Wow i honestly dont know how you have fitted a 48t on there you must have removed the plastic chain guide, my 43t has been rubbing agaisnt the chain guide top and bottom, did you also buy alonger chain.

[EEKAMOUSE]

Originally Posted by taninthai

Wow i honestly dont know how you have fitted a 48t on there you must have removed the plastic chain guide, my 43t has been rubbing agaisnt the chain guide top and bottom, did you also buy alonger chain.

Flipped chain guide upside down it was a prob but working! Lol its nice and punchy now

[Bladez]

Back to the exhaust... I am interested in opening up the stock muffler a bit. On the US models, after you take off the cosmetic endcap, do you have a plate that unbolts to remove the tailpipe from the muffler? On my Thai one, its all welded, but as per a previous post (see #1108), I see one that's bolt-on but I don't know if it was modified that way or not.

[Ed@Ford]

Originally Posted by Bake

Bill should have the new exhaust tips done soon. I will be testing one of those while he breaks in the 280.

EXHAUST TIPS??? Is this some sort of revised spark arrestor? Does it keep spark arrestor function?

[G19Tony]

http://antigravitybatteries.com/?page_id=994

I'm going to look into it more when I get home next week.

[SugarDust]

Originally Posted by EEKAMOUSE

Flipped chain guide upside down it was a prob but working! Lol its nice and punchy now

gotta pic?

[ramz]

Back to the exhaust... I am interested in opening up the stock muffler a bit. On the US models, after you take off the cosmetic endcap, do you have a plate that unbolts to remove the tailpipe from the muffler? On my Thai one, its all welded, but as per a previous post (see #1108), I see one that's bolt-on but I don't know if it was modified that way or not.

In post #1108, the rider and his friend removed the spark arrester tube from the bolt-on plate. This allows the exhaust to flow more freely, but you lose the spark arrester. Bill Blue's modified bolt-on piece will have a larger diameter tube WITH a spark arrester and perhaps a turned-down tip.

Pics of US bolt-on plate/tube/spark arrester here:
http://rickramsey.net/CRF250Lmods.htm
Scroll down two screens or so.

[Earthscape]

Originally Posted by Bake

The Bill Blue 280 big bore engine was up and running today. He said he completed the design for the second size engine. Bill's contacts in the business go pretty deep, if he pulls the trigger on these 2 big bore kits, it will happen relatively quickly. It's still his secret what size the bigger engine is, but I think it's about 320cc.
I got my Dobeck fuel controller today and will install it on my bike this weekend. Bill should have the new exhaust tips done soon. I will be testing one of those while he breaks in the 280. He says the cooling capacity can handle a 350, but there just isn't room to go that big.

Exciting stuff! Even though I have no plans to own a CRF250L right now because I love my KLX351, it's still great to see this happening. Did Bill ever consider doing a big bore kit for the WR250R? (Alternative option to the Athena kit for people...)

[eakins]

Originally Posted by G19Tony

http://antigravitybatteries.com/?page_id=994

I'm going to look into it more when I get home next week.

http://www.advrider.com/forums/showthread.php?t=789727

[Bladez]

Originally Posted by ramz

In post #1108, the rider and his friend removed the spark arrester tube from the bolt-on plate. This allows the exhaust to flow more freely, but you lose the spark arrester. Bill Blue's modified bolt-on piece will have a larger diameter tube WITH a spark arrester and perhaps a turned-down tip.

Pics of US bolt-on plate/tube/spark arrester here:
http://rickramsey.net/CRF250Lmods.htm
Scroll down two screens or so.

Ahh, thank you for clarifying that. My Thai muffler does not have that bolt on plate. The tail pipe is simply welded to the end of the muffler. I wonder which one is more free-flow? I have heard that the US bikes have a restricted ECU that can be swapped with a Thai ECU which is totally unrestricted. So I wonder if that would imply that your pipe would be more restricted than ours as well. Maybe I'll just try drilling a couple holes in the end. Or maybe a muffler shop here could cut out my tail pipe and weld a larger diameter one on.

Edit: Just found this; http://world.honda.com/CRF250L/chassis/page03.html which confirms that the US/Can model is different since it has a spark arrestor. This certainly makes our Thai mufflers more difficult to modify! I'll probably eventually bite the bullet and get an aftermarket pipe once I find one that doesn't have massive flat spots like a copy one I tested here, and isn't ridiculously loud.