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Just purchased 2015 Honda CRF250x

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Just purchased a practically new 2015 CRF250x. It has a bout 10 hours on it. I purchased it for $4400. The owner acquired it 6 months ago from a leftover dealer stock. I think I got a great price. I have a few questions. I am unfamiliar with the new CRf's. I always had the XR models. Here we go.

1) Is the early model valve problems fixed in 2015?

2) The manual shows some cylinder dowels that need to be greased. Is this really a regular maintenance item?

3) Fork oil change after the first three hours necessary?

4) Suspension disassembly and greasing schedule seems often(7.5Hrs)?

5) Maintenance charge  on the LI-Ion battery?

I am a causal woods rider and avoid water and mud. Maintenance is a priority unless it is excessive.Any additional tips other than mods you can give me? 

Thank You

 

 

Edited by liberty2701

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Congratulations on your purchase.

 

Being the 3rd owner, I've torn down and refurbished pretty much everything on my 2008 with the exception of splitting the engine's cases / bottom end.

After 1-1/2 years of ownership, I haven't found anything out of the ordinary that requires any special attention.

 

Initially based on a high strung 250R motocross race bike, for performance oriented off-road usage the X is quite a reliable and durable design.  

As with any bike, air filter maintenance is THE most important item.

 

Early 2004-05-06 CRF's had metallurgy issues with the valve seats, not the valves themselves.

Even with low hours, you should at a minimum check your valve clearances and take note of them.

If they require re-shimming, adjust and re-check them again after 20-30 hours or so.

If again they're out of tolerance, it's a sign you'll need engine work.

 

Some X owners are always looking for more horsepower, myself have a particular interest in suspension tuning.

Replacing suspension fluids, bleeding the cartridges and shock, recharging the nitrogen yearly is a sure bet to maintain it's best performance.

Suspension performance is something that gradually turns worse when neglected, things can become expensive when

worn bushings and gritty oil start wearing other components. (Showa parts in particular aren't as easy to locate as KYB parts)

 

Being a somewhat known design issue, in a few seasons I'd recommend replacing some seals in the fork's cartridges,

the ICS piston inner seals and lower cartridge/rod seals to be exact as these tend to leak and deteriorate the damping qualities.

 

Avoiding deep water as well, I still find my linkage/swingarm bearings need re-greasing twice a season.

(avoid direct point blank blasting with a pressure washer too)

 

The service manual suggest maintenance based on hours of use which is often 'overkill' meant for competition use.

If mostly recreational trail and off-road riding, I find it more realistic to judge required maintenance by the actual type of usage.

Say 3 'hard' hours of gnarly terrain riding where the engine worked hard requires an oil change more than say 8 easy hours of somewhat casual trail riding.

Amount of dust encountered on rides as well.

 

In general the X is well designed and easy to service but some things can be a bit of a hassle compared to simpler bikes.

To prevent binding/return issues, proper throttle cable(s) routing under the fuel tank can be tricky.

Versus an MX'er, the X also has more electrical wiring, a PAIR emissions device and overflow lines that clutter up the chassis

making access to the carburetor and shock not as straightforward as other bikes.

Edited by mlatour

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Thanks for the response. I will be changing the fork oil shortly. Picked up some Belray 5wt. Does it pay to go to a thicker oil since I weigh 220lbs or just increase the amount of the oil like the manual says?  You also stated to recharge the rear shock with nitrogen( I thought it should never leak unless you need a rebuild). I assume you picked up one of those small green tanks like they use in the HVAC business?  I just put an order in and should probably add some valve shims to the order. What sizes would you recommend to have on hand? What about greasing the cylinder dowels? I understand to do it on an engine tear down but as routine maintenance seems excessive. The manual also shows a cam tensioner stopper to remove the cam tensioner. Is this  tool really necessary?

Edited by liberty2701

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I'm not sure about the 'greasing cylinder dowels' you mention? I'll have to look it up.

 

Myself would not buy a complete valve shim assortment when perhaps only 1 or 2 are required and the great majority of them never used.

Plus, most HotCams and aftermarket shims are in 0.05 increments, genuine Honda shims are available in 0.025 steps for finer adjustment.

As mentioned, if the valves require shimming more than twice, you are due for engine work (valve faces and seats have worn)

 

If you plan on only changing the external fork oil only, go the extra step and do the cartridges as well (more important)

Search YouTube for the TBTRacing KYB fork how-to videos, these Showa forks are very similar in design.

Cartridge forks are designed to function on 5W fork oil, tuning with oil weight is mostly done with simple orifice

type forks (older 'right side up' tubes) where internal and external adjustability is very limited versus modern cartridge forks.

 

The oil volume mentioned in the manual only affects the last 1/3rd of the stroke, controlling the progression near bottoming

but doing nothing at all to initially support more weight, only springs support the bike and rider's weight.

 

The X suspension initially designed for an average 150-160lbs rider in mind, at 220lbs you will require stiffer fork/shock springs

of at least 1 rate stiffer in forks (.44) at about 4 rates stiffer for the shock (5.8) depending on your type of riding,

otherwise the suspension will ride deeper in the stroke, making for a mushy yet harsh ride and messing up the bike's handling.

With a drastic increase in spring rate (shock) internal valving may very likely need stiffening as well as stiffer springs speed up rebound.

 

Nitrogen 'migrates' thru bladder over time, meaning you could still read and/or re-pressurize at 140psi at the valve but

some nitrogen has transferred into the 'oil' side of the shock. I've seen it happen on a few bikes even when not in use / during prolonged storage.

That's why I bleed the shock yearly and re-pressurize the bladder (myself use air versus nitrogen via a 0-300psi mountain bike pump),

even with a good bladder I've always found some pressure build-up in the 'oil side'.  (bubbles = cavitation = mushy damping)

 

Edited by mlatour

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Greasing cylinder dowels?

I bought a  05 in 2014 and redid the top end, no issue with cylinder dowels.

My experiences have been similar to the previous posts; for trail riding these bikes don't seem much different than XRs, but they have far better performance. :thumbsup:

I converted mine from a AZ bike to a one for tight gnarly PNW trail riding and it is working quite well. In spite of the long wheelbase, high weight, and lazy steering rake the bike will do quite well on tight gnarly single track, but it is more tiring to ride than my lighter weight XR. When I first got it I was reluctant to take it on a ride on tight trails, but after more careful set up it has been working quite well this past summer.   

I lowered the bike and revalved the forks and shock.

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All great info. Just a few follow up questions.  

1) I thought air in the rear shock was  a big No?

2), I will be changing the fork oil. What brand fork springs are good (Racetech)? What about the seal driver tool and spring compressor. Are these necessary?

3) Can I just adjust the rear shock preload for my weight?

4) Are you allowed to use a double valve shim to get were it is needed?

Edited by liberty2701

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While Nitrogen is preferred for it's stability, air will do just fine for non-competitive usage.

Monitoring pressure build-up during a motocross track day, the most I've seen is a 10psi increase on my YZ125.

 

RaceTech fork springs would be my choice but as long as the rate is accurate and length correct any brand will do.

Specific fork tools (cap wrench, seal bullet/driver, H-tool, graduated cylinder)

all make the job easier but more importantly prevents damage to very expensive components versus using the wrong tools.

 

No matter how much you crank up the preload rings, the stock shock spring will remain too soft for you.

 

Not sure what you mean by 'double valve shim' ?

Edited by mlatour

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Can i stack two together if needed to get the correct valve leash. I would like to order some shims to have on hand and thought it would be best to just order a bunch of the thinnest ones. What is the H-tool?

Edited by liberty2701

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Valve shims can't be stacked, you must use the proper sized one.

In a pinch you can sand down a slightly thicker one to the desired thickness.

 

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19 hours ago, liberty2701 said:

All great info. Just a few follow up questions.  

1) I thought air in the rear shock was  a big No?

2), I will be changing the fork oil. What brand fork springs are good (Racetech)? What about the seal driver tool and spring compressor. Are these necessary?

3) Can I just adjust the rear shock preload for my weight?

4) Are you allowed to use a double valve shim to get were it is needed?

1) For best results the shock gas should be dry and inert, several industrial gasses qualify such as Nitrogen, CO2, helium. Since air is mostly Nitrogen that gas is readily available as an industrial gas, and is often used. Paint ball guns use CO2 and I charge my shocks from a paint ball cylinder with an air tool regulator and a lossless chuck. Cheap and easy. The regulator goes high enough for my CRF250X shock but not high enough for XR shocks but I haven't had any problems with XR shocks at the lower pressure. The setup is has a belt clip for use with air tools and is small enough to pack in my PU for tire inflation.  Twin chamber forks also pressurize the fork suspension fluid but most use a pressure spring and piston.

2) I've used RaceTech springs on several projects and their rates are very close to spec while some OEM springs seem to have a  lower rate than spec. 

3) Sag measurements indicate if the spring rates are appropriate, I use Dwight Rudder's offroad percentages rather the the common MX because I ride off road. I've found using metric to be far easier and more accurate than dealing with fractions. :banghead:

4) I don't understand the double shim: Most stacks will have multiple shims of the same size in the first part of a stack. There are multi stage shim stacks that are preferred for off road while MX seems to use single stage stacks, each stage is separated from the adjacent by a "pivot" shim.  Racetech's Suspension Bible has a lot of great info on how suspension works. 

Aftermarket valve shims are at every other OEM shims so less precise in setting clearance but usually OK.  I bought an aftermarket kit and it has worked for me. And I have Dremel sanded a shim to make it thinner when I was extending my riding season with an engine that had a receding intake valve, I wouldn't do that for a more permanent shim. 

 

Edited by Chuck.

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I am going to change the oil in the forks and rear shock. Being that the bike has 10 hrs on it, should I replace all seals and bushings or just the oil? I also have a compressed air dryer to charge the rear shock properly.  

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At only 10 hours (of likely off-roading rather than MX'ing) the bushings should  be just fine.

 

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It was ridden on a guys farm.  I guess a visual inspection will indicate wear? Should they be measured with a caliper?

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Never heard of measuring them, but yes visually you'll see of they're due.

Even with low hours, you'll be surprised how nasty suspension fluid can get. (metal glitter in oil, foamy)

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