Jump to content
Sign in to follow this  

BUILD A KILLER WOODS BIKE FOR UNDER $3K (Pics inc)

Recommended Posts

I sold my $11000.00 KTM for financial reasons and was ready to call it quits, untill I found a 01 CR 250 for $1200.00.

I thought, I'd keep riding for the fun of it and build a cheap beater woods bike, the 00 or 01 has good low end and I knew I could modify the power valve to tame the hit some.

So, on to the project.   The 01 was in pretty good shape, it had some extras but need a few tweeks to make it more trail friendly.

The bike came with the following items, fmf shorty silencer, skid plate, bark busters, fat bars, radiator guards, fresh top end and clutch with a Hinson basket, 13/51 gearing.

I did need to rebuild the water pump and grease the link, etc..but everything else was in good working order.

I knew what I wanted to tweek, mainly get the suspension woods friendly and massage the power to gain more low end grunt and tame the hit some....replace some worn items.

Here is the parts list:

FMF Gnarley pipe............$200.00

Torque spacer....................$25.00

Intake spacer.....................$25.00

36mm as keihin...............$200.00

Boyseen rad valve...........$150.00

12 oz FWW........................$60.00

braded brake lines............$70.00

pads..................................$50.00

Rotors.............................$120.00

Moose ez clutch.....lever...$35.00

Overflow tank...................$12.00

1.6 radiator cap................$25.00

18'' rear rim....................$120.00

Spoke set.........................$95.00

Trials tire.........................$120.00

Tubless 18''....................$100.00

Pirelli MT 16 front.............$80.00

.46 fork springs................$90.00

fork.shock oil...................$30.00

5.3 Shock spring...........$110.00

CR 125 clutch springs (3)...$10.00

Total: $1727.00 (under $1800.00)

For under 3K I have a great handling woods bike that will last me as long as I want to thrash it....I think this was a good investment.

I had almost 11K in my 12 300XC and it was a slug in the woods...good motor but handling and suspension, NOT good!

Mods:

Fab a adjustible spring tensioner for the power valve..... spring from ace hardware.

Soften clutch pull with softer springs...Still testing, but Cr125 springs work...either 2 or 3.

Pv governer springs work well 2 only, combo of 2 stock, 2 cr125, 2 gov springs work great but some slipping in higher gears 4th/5th

Revalve the shock and forks

build a overflow tank

Seal the air box...water proof the lower sections, add a single drain hose on one side

Install above parts.

Revalve.

Results:

The bike is awesome! I can make it super tame or hit very hard off the bottom (or any where in between) with a quick adjustment of the pv tensioner.

The motor has great low end torq, enough to softly pull up greasy off cambers without lighting up or spinning the tire.

With the suspension plushed out and the motor easier to control, I can attack any sections we ride far better than I could with the 11K ktm.   Guys I ride with say I'm much faster on this bike and I feel faster, but the best thing is I'm far more confident at speeds than I was on my last bike.

The valving set up is listed after the pics, I did make a change since but it should be ball park for most.

On to pics

 

DSCN0159_zps983ee77a.jpg

DSCN0163_zpse1e1ed61.jpgDSCN0165_zps1eed4c3c.jpgDSCN0146_zps240790ef.jpgDSCN0153_zpsce0d5b66.jpgDSCN0148_zps38911d0e.jpgDSCN0158_zpsa5cab6b4.jpghttp://i14.photobucket.com/albums/a315/moto9/DSCN0163_zpse1e1ed61.jpg

 

DSCN0169_zps7f5f727b.jpg

 

DSCN0170_zps23045150.jpg

 

A class vet rider, 190lbs

3 wt both inner/outer chamber, 300cc oc .46 springs
BV
20.10
12
20.10 (5)
18
16
14
12
10
9
MV
20.10x3
17.10x2  float 0.20
REB
20.10
12
20.10 (6)
18.10
17.10
16.10
14.10
12.10
11.30

 

SHOCK 5.3 spring, 3wt, 165psi
COMPRESSION
44.20
38.15
44.20--4
44.15--4
37.15
30.15
44.15
42.20
40.20
38.25
36.25
34.25
32.30
30.30
28.30
26.30
24.30
22.30

REBOUND
40.20
38.10
40.20- 14
40.45
26.10
40.30
38.30
36.30
34.30
32.30
30.30
29.30
28.30
27.30
26.30
25.30

Hope this helps other riders that want to build a decent low-er cost woods bike .
 

 

 

 

 

 

  • Like 8

Share this post


Link to post
Share on other sites

Awesome build. Great choices in parts and set up,

Im considering a magura clutch set up for my 04 cr250 the clutch pull is stiffer than id like, i love a one finger clutch. I dont know if 125 springs is the best idea for abusing the clutch. May lead to some slipping.

Share this post


Link to post
Share on other sites

Awesome build. Great choices in parts and set up,

Im considering a magura clutch set up for my 04 cr250 the clutch pull is stiffer than id like, i love a one finger clutch. I dont know if 125 springs is the best idea for abusing the clutch. May lead to some slipping.

Slipage is ok for trail, the best thing about the Rekluse is it's ability to slip better that the human hand.

Magura...yes...had one on my 450F, but just a reminder...I'm trying to stay as cheap as possible...maybe sometime down the road I'll get one.

My selection in parts were what was needed..if I can get by cheaper I will.

Besides, a clutch can take quite a lot of abuse and is fairly cheap and easy to replace.

Edited by moto9

Share this post


Link to post
Share on other sites

I think the way you trimmed the side panels looks cool. Do you find that you get more dirt sprayed up on you as a result? I ask because I ride in a lot of muddy areas and don't want extra mud/dirt up on me.

 

I have a little more in my '01 than you do, but hey it was all worth it.

 

On the clutch,  I would highly recommend you put the proper springs back into the clutch to keep it from slipping & burning up.

Share this post


Link to post
Share on other sites

I think the way you trimmed the side panels looks cool. Do you find that you get more dirt sprayed up on you as a result? I ask because I ride in a lot of muddy areas and don't want extra mud/dirt up on me.

 

I have a little more in my '01 than you do, but hey it was all worth it.

 

On the clutch,  I would highly recommend you put the proper springs back into the clutch to keep it from slipping & burning up.

It's usually very muddy here to, a lot of guys don't run panels at all for added grab points.

I don't think I get any dirtier with the cut panels.

As for the clutch, I'm not worried about it slipping some and I'll bet I get a year or more out of it with out any issues.

I still have the stockers on the side which are in good shape, besides, any bike with a rekluse slips the clutch.

Share this post


Link to post
Share on other sites

Your suspension valving is kinda odd...particularly your low speed circuits. Looks like you like a very light low speed, and stiff high speed. 

Did you get to this valving stack purely on your own or did you work with someone to get this stack?

Share this post


Link to post
Share on other sites

Slipping the clutch at and around idle is what the rekluse does.  What were worried about is full throttle higher rpm without the right springs itll slip.  That's far different than the slipping your talking about with the rekluse. 

Share this post


Link to post
Share on other sites

Your suspension valving is kinda odd...particularly your low speed circuits. Looks like you like a very light low speed, and stiff high speed. 

Did you get to this valving stack purely on your own or did you work with someone to get this stack?

A little help but mostly through testing.

The fork is very plush on the roots and rocks on the tight tech single track I ride.

Share this post


Link to post
Share on other sites

Slipping the clutch at and around idle is what the rekluse does.  What were worried about is full throttle higher rpm without the right springs itll slip.  That's far different than the slipping your talking about with the rekluse. 

I'm still testing, I got in a 4 hour ride yesterday and could not tell any difference in performance.

I Took a measurment on the new fibers when I r&r the springs and will keep an eye on the plates to see if they start to wear prematurely.

Share this post


Link to post
Share on other sites

I think you'll be fine, for me I don't think it would be too good.  Im pretty heavy and ride the 250 in a lot of high load tracks,  big hills, deep soil, sand etc.  I like the 125 for harder pack and the 250 for the deep stuff since it can pull right through it all.  If your doing a lot of trail work your typically not full throttle very often and will probably never have an issue.  Keep us posted though its a cheap experiment either way. 

Share this post


Link to post
Share on other sites

A little help but mostly through testing.

The fork is very plush on the roots and rocks on the tight tech single track I ride.

Gotcha! I may give that stack a try on my 02 cr250. I see you are using 3wt oil all around, what oil are you using?

Share this post


Link to post
Share on other sites

Can you explain your power valve mod and how it works?  You are the first person I have seen do this and I am curious about how it works.

I drilled a hole in the end of the left side sub exhaust valve and as you can see in the pic one in the end of the bolt.

The ends of the spring are "G" shapped and slip into the holes.

I turn the bolt clockwise to put positive tension on the PV which holds it closed longer, making the power more mellow and giving it a softer later hit.

Turn the other direction and it opens quicker making it more explosive off the bottom..or aywhere in between.

I ride mostly greasy tech single track, so the mellow torquey power makes it easier to controll the bike.

 

I have a cool design for one that you can just reach down and click either direction...even adj on the fly... but never got around to having one machined.

Edited by moto9
  • Like 2

Share this post


Link to post
Share on other sites

Gotcha! I may give that stack a try on my 02 cr250. I see you are using 3wt oil all around, what oil are you using?

Maxma 3wt shock oil, it's easier to use the same oil for both because I take straight out of the bleed tank...de-gassed.

Share this post


Link to post
Share on other sites

I drilled a hole in the end of the left side sub exhaust valve and as you can see in the pic one in the end of the bolt.

The ends of the spring are "G" shapped and slip into the holes.

I turn the bolt clockwise to put positive tension on the PV which holds it closed longer, making the power more mellow and giving it a softer later hit.

Turn the other direction and it opens quicker making it more explosive off the bottom..or aywhere in between.

I ride mostly greasy tech single track, so the mellow torquey power makes it easier to controll the bike.

 

I have a cool design for one that you can just reach down and click either direction...even adj on the fly... but never got around to having one machined.

 

 

Wow!  Good idea!

Share this post


Link to post
Share on other sites

I drilled a hole in the end of the left side sub exhaust valve and as you can see in the pic one in the end of the bolt.

The ends of the spring are "G" shapped and slip into the holes.

I turn the bolt clockwise to put positive tension on the PV which holds it closed longer, making the power more mellow and giving it a softer later hit.

Turn the other direction and it opens quicker making it more explosive off the bottom..or aywhere in between.

I ride mostly greasy tech single track, so the mellow torquey power makes it easier to controll the bike.

 

I have a cool design for one that you can just reach down and click either direction...even adj on the fly... but never got around to having one machined.

This looks like a really useful and clever modification, I would like to do the same, was it easy to drill the hole in the end of the left sub exhaust valve and how close to the end did you drill, can you see this with the side cap off and the spring out ?

So in effect you can apply some preload in either direction or neutral effect, that is working for (adjusted one way) or against (adjusted the other way) the small spring on the other side and of course the governor  ? just trying to clarify how it works, thanks for sharing such a cool idea !

Edited by mike500

Share this post


Link to post
Share on other sites

This looks like a really useful and clever modification, I would like to do the same, was it easy to drill the hole in the end of the left sub exhaust valve and how close to the end did you drill, can you see this with the side cap off and the spring out ?

So in effect you can apply some preload in either direction or neutral effect, that is working for (adjusted one way) or against (adjusted the other way) the small spring on the other side and of course the governor  ? just trying to clarify how it works, thanks for sharing such a cool idea !

It was very easy, the sub valve is held in by a circlip, (as you probably already know)  so it can be easily removed out the side.

I flattened the top side on the bench grinder so it was easier to set a punch mark and drill the hole.

Use a bit just large enough to accept the spring wire and place it at the very end....there's plenty room.

I did the same to the bolt, you'll have to work a little with the bolt length so the're is no rubbing or excessive spring bind.

Maybe a slot in the bolt would work better.

I drilled and taped the cover and threaded the bolt thru with a lock nut on the outside.

And yes, it preloads the PV, You don't need much preload to have an effect.

Edited by moto9

Share this post


Link to post
Share on other sites

A little help but mostly through testing.

The fork is very plush on the roots and rocks on the tight tech single track I ride.

Hey moto I'm sure this will be very helpful for others as it has been for me.

I can attest to this as I have a similar stack with help from moto along with the .46 fronts and 5.3 rear for my 195 lb setup. It is much better then stock! Still in the initial testing stages! Only difference was my front has showa 5wt in front and the 3wt in the rear.

Ever get a measurement on those forks moto?

Aside from the rekluse the suspension mods have been the best things I have done to my 01

Edited by izcain

Share this post


Link to post
Share on other sites

Your suspension valving is kinda odd...particularly your low speed circuits. Looks like you like a very light low speed, and stiff high speed. 

Did you get to this valving stack purely on your own or did you work with someone to get this stack?

 

A little help but mostly through testing.

The fork is very plush on the roots and rocks on the tight tech single track I ride.

 

Does the single face shim act sort of like a bleed shim? 

 

How does the suspension feel when you get into faster 3rd gear trails?

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Reply with:

Sign in to follow this  

×