2007 crf250r 3 months to season prep!

[matty86suk]

Hey folks,

I picked up a low'ish hour 2007 250r that is am gonna race in this years HS season on Vancouver island. First race is 22nd of March, so the clock is ticking to get the bike ready and to get some practice hours on her.

About my self. I'm 34 years old, I'm a marine technologist with a highly technical background. I started riding dirt bikes about 18 months ago, I'm not sure but I thinknim a C rider lol. I'm fit and have been dry land training 5 days a week, riding on weekends. I'm not a total newb on the bike, I ride a klx250 daily and have owned a cr125, 250, kdx220, klx400. I'm also very mechanically inclined and will be doing 95 percent of the wrenching, I will send the forks out to be re-shimmed, unless I get brave. So the bike...

The bike is in good shape, no loose bearings, engine runs good but could use a carb clean. Clutch needs replacing but the basket and inner hub are good. I'll try to post pics as the prep work goes on for anyone's intetest and a way for me to catalogue any work. So the list of must do's and want to do's...

Must do

-protection(handguards, slid plate)

-grease all bearing on chassis(swing arm, steering, etc)

-clutch kit

-couple new air filter(filter is good but I will be anal about this)

-5 gallons of engine/tranny oil(what's a good oil?)

-case of filters

-top end week before season with some run in time

-check valves analy(they are currently in spec)

Wants

-rekluse auto clutch or Hinson race clutch, still on the fence, I might just get the exp with the clutch kit them decide if I want the zstart or pro.

-big bore, maybe after this season

Anyways, any tips, hints or suggestions are welcome. I'm new, but not too newbish

Bike

Matt

[LoonRider]

Suspension before anything else. Send those forks out to get revavled and sprung for your weight

[DamnitJuice]

Pick up a stainless oil filter and never buy an oil filter again. Clean it when you do an oil change.

[matty86suk]

Suspension before anything else. Send those forks out to get revavled and sprung for your weight

I keep hearing this. I punched in my weight, age, ect in race techs calculator. I am good on the fork springs but I need to go up to a 6kg rear spring. I am gonna do the rear spring before the season but will wait on the revalve until mid season break or over next winter. I've never raced before and think I need to feel it out before going all in. Who knows I might be on another bike next season. I'm gonna focus on finishing every race and my fitness, plus I only have a 1200 dollar budget for upgrades and maintence until mid season break, and I need a clutch, piston kit, rear spring and armour(and most likely more). I'm gonna do a full grease routine over the week, hopefully no surprises.

[adam8781]

stock jetting sucks, Do some research on how to fix the stock carb.  For the type of racing you are doing I would also suggest oversize radiators. Add a tooth or two to the rear sprocket. Rest of the list seems pretty good. Keep the updates rolling.

[problem_child]

flush/bleed the brake lines

 

Getting new oil/seals/bushings for your suspension wouldn't be a bad idea

 

oh yeah and a bike stand  ?

[bucket list]

I also picked up a very low hour 07 last winter, raced a couple of mx's (was a pro back in the late 70's) now I'm just setting it up to trail ride, might try one of those HS.

With your background, I wouldn't be afraid to reshim the forks yourself. I did mine because it was beating the crap out of me on braking bumps. It took a few tries, but I settled on a slightly stiffer spring .47 , reducing the oil volume to 350cc and removing 1 face shim off of the mid-valve, so a softer low speed comp. Now their plush!! I hardly feel anything through the handle bars now. Sounds like your on the right track with the other stuff. I'd be glad to help with other stuff, oh and wheres that first HS?

[Tough Noogies]

Awesome!  Good luck with the build!  It sounds like you and I are attacking the same things near the same time for almost the same reason!  Hahaha... 

 

Here's a link to my build, just in case you want to check it out for product comparisons or ideas (I've done some protection adding, already, and will be going through the motor soon).  I'll post my current mod list in the next day, or so.   https://www.thumpertalk.com/topic/1118550-07-offroad-build/ 

 

I don't want to thread jack, though!  So, I have to say, I dig the white plastics and seat!

 

As far as tips, take a look at the swingarm pivot bolt early on.  Sometimes, that bolt swells a bit with corrosion and turns into a real bear to get out.  If yours pops right on, nothing to worry about and you can move on quickly.  If it binds real bad, plan to tackle it when you have a lot of other components off the frame and engine at once.  My 07's previous owners must have never greased the thing.  It took 16 hours of wailing with an engineers hammer over a few days and a lot of penetrating fluid to get it out (seriously... air hammers, and other methods didn't work... I was about 20 minutes from a sawzall and a new swingarm when it finally started to give)!  ?

 

Best of luck while building!  I'm subscribed to see what you do!

[matty86suk]

flush/bleed the brake lines

Getting new oil/seals/bushings for your suspension wouldn't be a bad idea

oh yeah and a bike stand ?

I made one out of wood, oh yah I'm cheap were I can afford to be...:)Seals look good currently. But I watch them closely.

[Racer132]

1.suspension

2.jetting

3.protection stuff

4.decent tyres

5.hydro clutch

 

id just put a stock clutch back in it,they work fine!

but wouldnt even bother riding off road on a mx bike without the suspension being done first.it will beat u up really quick!!

also a full service and re-grease of every moving part!

 

then just ride the thing

 

cheers chris

[matty86suk]

I also picked up a very low hour 07 last winter, raced a couple of mx's (was a pro back in the late 70's) now I'm just setting it up to trail ride, might try one of those HS.With your background, I wouldn't be afraid to reshim the forks yourself. I did mine because it was beating the crap out of me on braking bumps. It took a few tries, but I settled on a slightly stiffer spring .47 , reducing the oil volume to 350cc and removing 1 face shim off of the mid-valve, so a softer low speed comp. Now their plush!! I hardly feel anything through the handle bars now. Sounds like your on the right track with the other stuff. I'd be glad to help with other stuff, oh and wheres that first HS?

Here's some info on the series I'm riding in...

http://www.dirtbiker.ca/vihss

Also I adjusted the inputs on the RT site on got different numbers for springs, by what race tech indicates I'm in the ball park for weight. Have any links on what you did with your valve stack??

[matty86suk]

I picked up a used FSM as well

[bucket list]

Here's some info on the series I'm riding in...

http://www.dirtbiker.ca/vihss

Also I adjusted the inputs on the RT site on got different numbers for springs, by what race tech indicates I'm in the ball park for weight. Have any links on what you did with your valve stack??

https://www.thumpertalk.com/topic/327668-diy-04-450-suspension-re-valve/page-86

 

Thanks for the link to the series Matt. As for my revalve, i just read Racetec's suspension bible and alot of research, talking to others that have done valving and took a stab at it myself. If you can understand how it all works and what your bikes doing that you don't like.  You can work towards what will make it better for yourself. In the CRF450r forum a guy called theDogger has a 99 page thread with some good info if you got the time to go through it. Adjusing that mid-valve float made a big difference in feel.

https://www.thumpertalk.com/topic/327668-diy-04-450-suspension-re-valve/page-86

[The Inquisitor]

I picked up a used FSM as well

Get a Clymer manual.

Put on an hour meter if you don't already have one.

Log your ride hours, fluid changes, etc.

I use Maxima products and check engine oil every ride. I replace engine oil, filter and tranny at 10hrs max or sooner if the engine oil starts looking dark.

I use no-toil and flo air filter's with the flo skin. Extra set in a Rubbermaid and change frequently.

Recently installed an 110z stealthy fly wheel weight. Could have gone 13 or 15 and way cheaper than a recluse.

My buddy recently put on a 280 Athena with a pro circuit header and silencer on his 09 250x. Dramic change but not sure I would do it on my r for the $$$..

Hope to make it over to the island for some ride this summer

[adam8781]

factory service manual is much better than a clymers.

 

 

And for the oils, cool thing about the crf is seperate oils. Run a cheap oil in the transmission, \shell rotella triple, atf type f or atf+4.  And whatever you like in the motor side.

[Tough Noogies]

Matty, I totally recommend calling up Factory Connection and asking them about a recommended spring rate.

I found that using RaceTech and MX-Tech together for Internet calculations helped, but getting the confirmation on a blend of the spring rates I was toying around with buying made me positive I was buying the right springs. In fact, I didn't even buy from them at the time (found a deal elsewhere over the summer), but I liked them enough to send them the whole kit over this last Xmas.

I agree, too - couldn't live without my OEM service and operators manuals.

[matty86suk]

factory service manual is much better than a clymers.

And for the oils, cool thing about the crf is seperate oils. Run a cheap oil in the transmission, \shell rotella triple, atf type f or atf+4. And whatever you like in the motor side.

I was hoping to run rotella t6 in the crf as I use it in my KLX and I have about 3 gallons left of it. I haven't really check if the T6 is comparable with the crf engine side. T6 comes on sale all the time around here so that is a bonus of the rotella

[adam8781]

I was hoping to run rotella t6 in the crf as I use it in my KLX and I have about 3 gallons left of it. I haven't really check if the T6 is comparable with the crf engine side. T6 comes on sale all the time around here so that is a bonus of the rotella

 

You can run the t6 in either side. Great oil don't be afraid to use it. I ran t6 on and off, but ultimately I ended up with rotella triple in the 5 gallon pails. Most cost effective.

Edited January 15, 2015 by adam8781

[bucket list]

You can run the t6 in either side. Great oil don't be afraid to use it. I ran t6 on and off, but ultimately I ended up with rotella triple in the 5 gallon pails. Most cost effective.

Agree, I've run both, although I tried ATF in the trans. I change trans oil often, cause it gets all silvery black.

[matty86suk]

Agree, I've run both, although I tried ATF in the trans. I change trans oil often, cause it gets all silvery black.

I was running ATF in my cr250 and KDX, I'm anal about oil changes, so every 5-8 hours I'll change it. Id obviously liek to keep it common for the crf trans and engine so T6 it is.

 

Matty