Winter Project CRF

Herpderplol

BRRAAAAAAAAAPP
Aug 22, 2012
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Dickinson, ND
Most of you should know that I now own a 2006 crf250r. Sold the blaster, was skeptical though, because a 13 year old kid bought it. Scrawny too, I was surprised he could pull the HD clutch lol

Anyhow, I owned the bike for a little over a month before we brought it to our house, it was stuck in MN since we drove the car the day we bought it. It was super hard to start, maybe 25-30 kicks. checked valve clearance and bam I had it fixed a week later.

My dad and I saw a video or photo somewhere of a bike with a polished frame and decided to do that over the winter. So here is a little of my progress.

Started with the plastics coming off


Then I took the ass end of the bike apart (dropped a shock linkage bearing.... oops)


Front off as well


Test run with the buffer because we just bought it


Motor out, did a good scrub down on the bike
 
looks good any performance mods planned?
Not really. It already has plenty of power and speed.
Im going to play with the gearing, think i have 14.53 and im going to stock 14.51 just because its stock.

I would rather choose life than death when riding this lol. might end up doing valves. i need to adjust again or something

PO said he rebuilt it about 3 races before he sold it to me. locked up in a race, fixed it and then found a 2013 yz125
 
This has been moving at a much slower rate of speed than I had hoped. I wanted to do a lot more polishing over the break but I had only gotten the polishing pads on christmas eve. I ordered a set of 3 from amazon and they worked pretty well. But they all only lasted about 30 minutes each before they tore apart. So I'm mailing them back to amazon for some replacements :D

With the new pads, I was able to polish the right side much better than the left, so now I'm going to go back and redo the left side. Still working on the part my triple clamp goes through... Has a few interesting bends that are hard to hit with a 7.5 buffing wheel....

Pictures soon

Not really. It already has plenty of power and speed.
Im going to play with the gearing, think i have 14.53 and im going to stock 14.51 just because its stock.

I would rather choose life than death when riding this lol. might end up doing valves. i need to adjust again or something

PO said he rebuilt it about 3 races before he sold it to me. locked up in a race, fixed it and then found a 2013 yz125
Also, found out stock gearing is 13:51. Currently I have 13:53 and I'm ordering 14:51.
If I don't like it, I will order a 13 before I get more than 5 hours on the new chain and stuff.
 
Finished polishing. Might do a little more up near my triple, but it's hard to fit a 7" wheel in the smaller spots.




My head cover I painted black, and red for the lettering. 500 degree paint, 2000 degree clear coat



Wanted to wash parts. We dont have an outside sink or parts cleaner. So I scrubbed it in my shower :p
 
Here's the deal with this engine. The exhaust valves are SS and the intake valves are titanium. The seats are sintered metal. The titanium valves don't work well with the seats. They get beat up pretty fast. You have two options. Copper seats (stupid expensive) or stainless valves. The stainless valves will slow you down a bit but if you're not a pro expert rider it's not an issue. Stainless valves weigh 10 grams more than titanium so you'll also have to upgrade the springs. My best advice (before you pop a valve head off and destroy everything) is to pull the head and change the valves and springs to a Kibblewhite set up. The kit works great and will save you a bunch of problems. If you go this direction, remember your uncle Ken loves you as the valve seats will need to be cut. This is not plug and play. While you're in there, check the cylinder clearance and change the timing chain. A bad chain will destroy your crankshaft. It's not a Blaster boss. It's one cylinder of a formula one race engine and needs to be treated as such. These engines are built in a very high state of tune so maintenance is key. If you pop a valve head, you're looking at $3000 - $4000 to fix it. Cases, cylinder, head, head components, oil pump.....the list goes on and on.
 
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i was a Honda guy for life, but finally sold my CRF450 because of the valve issues. it was a nightmare...and I have heard the 250s are even worse.
great bikes, dont get me wrong...the throttle hit is like no other on them Hondas, but i was over the whole kicking thing.
i would also recommend switching over to the kibble white valves. i have heard they completely eliminate the valve problem that CRFs are known for. pricey repair, but well worth it. I would have done it on my CRF450 but decided to put the money towards something new...so I got a KTM450SXF. best investment i have ever made. the bike rides like a dream...and the chicks flock to it :D
 
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Here's the deal with this engine. The exhaust valves are SS and the intake valves are titanium. The seats are sintered metal. The titanium valves don't work well with the seats. They get beat up pretty fast. You have two options. Copper seats (stupid expensive) or stainless valves. The stainless valves will slow you down a bit but if you're not a pro expert rider it's not an issue. Stainless valves weigh 10 grams more than titanium so you'll also have to upgrade the springs. My best advice (before you pop a valve head off and destroy everything) is to pull the head and change the valves and springs to a Kibblewhite set up. The kit works great and will save you a bunch of problems. If you go this direction, remember your uncle Ken loves you as the valve seats will need to be cut. This is not plug and play. While you're in there, check the cylinder clearance and change the timing chain. A bad chain will destroy your crankshaft. It's not a Blaster boss. It's one cylinder of a formula one race engine and needs to be treated as such. These engines are built in a very high state of tune so maintenance is key. If you pop a valve head, you're looking at $3000 - $4000 to fix it. Cases, cylinder, head, head components, oil pump.....the list goes on and on.
Good info to know. I will probably pull that apart in the coming weeks.

I also assume to replace the timing chain that requires the cases to be split?
Which I would probably do after the rest of the bike is together and my mess is cleaned up
 
Good info to know. I will probably pull that apart in the coming weeks.

I also assume to replace the timing chain that requires the cases to be split?
Which I would probably do after the rest of the bike is together and my mess is cleaned up

Could you not just break the chain to install it rather than splitting cases?
 
Paid the good man today. Ended up going with all four valves rather than just intake. Ken talked me into it.

Hopefully I have that back by Thursday so I can begin to assemble next weekend.

Also because my rear spokes were loose, I borrowed a truing stand from my friend. The wheel was straight so I tried to tighten the spoke ends. Half of them went okay, the other half I couldn't hold with a square jaw vise grip so I solved my problem the fun way. By that, I mean i put a cut-off wheel on a grinder and cut every one in half. Obviously a new kit is on its way as well.
 
New radiators and mishimoto hoses
20160309_214258.jpg

Motor waiting to pop the flywheel off. I didnt want to order the puller, mechanic at honda left his in Bismarck today so he tapped two pry bars under the wheel to create tension. Then used a brass hammer to hit the crank end. I have the head on and set the valve clearance. I will check it once more before i put the cover on
20160309_214304.jpg

Front end on. Motor and swinger will be next when its ready
20160309_214310.jpg

Wheel going together. Supersprox 51T red sprocket. New stainless spokes. STI extreme duty tube. Kenda Millville 2 tire.
20160309_214317.jpg
 
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When ur coming home from work and u know ur parts are gonna be waiting for you is the best. Nice build so far I'm tuned in
 
When ur coming home from work and u know ur parts are gonna be waiting for you is the best. Nice build so far I'm tuned in
Or if they are sitting at your door and I have to make a mad dash home between school and work because i dont want them on the steps all night haha

Tomorrow night i have off, hope to throw the engine in before school tomorrow. possibly kick it over tomorrow night. wont be 100% but maybe run-able.
 
The motor is together. Torqued the flywheel and cam caps.
I tried to get the motor in this morning but I couldn't seem to get it in...
 
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