Cam change check list

Bought a Stage 1 hotcam the other day and just putting together a checklist of things i might need to do the job.

Thought i might ask you guys to help out :prof:

The bikes a '07 YZ250F with about 6 hours on it (just for interests sake)

*Hotcam

*Shim kit

*Mineral based oil for run in (suggested)

*Torque wrench

*Feeler gauges

*Sockets

*Screw driver

Is there any need for gasket replacement???

Well thats all i can think of, what have i forgotten? Any tips for doing the job?

Thanks guys,

CrankR.

good quality torque wrench matco, snap-on, cornwell ,mac tools and also what I did when I replaced the stockers wit hotcams I replaced both c-clips. Also get some assebly lube and lube all lobes and buckets

Even though the manual says to use assembly lube, I don't like using the stuff in order to avoid contaminating the clutch with moly. I'll use a good quality dinosaur oil instead. No head gasket needed. you're not removing the head.

Things to have that you haven't mentioned:

Dino oil (instead of assy lube)

plastigage (to make sure the caps and cams have the proper clearances.)

String or a coat hanger (to hold the cam chain from falling into the engine.)

New timing chain. (cheap insurance, but with 6hrs on the engine, I'd probably skip this)

Tips:

1) Take the time to use the plastigauge. It will save you major $$ later if something is too tight right now.

2) Use plenty of oil on the journals and mating parts (cam lobs, buckets, shims, valves.

Even though the manual says to use assembly lube, I don't like using the stuff in order to avoid contaminating the clutch with moly. I'll use a good quality dinosaur oil instead. No head gasket needed. you're not removing the head.

Things to have that you haven't mentioned:

Dino oil (instead of assy lube)

plastigauge (to make sure the caps and cams have the proper clearances.)

String or a coat hanger (to hold the cam chain from falling into the engine.)

New timing chain. (cheap insurance, but with 6hrs on the engine, I'd probably skip this)

Tips:

1) Take the time to use the plastigauge. It will save you major $$ later if something is too tight right now.

2) Use plenty of oil on the journals and mating parts (cam lobs, buckets, shims, valves.

Dinosaur oil hey, i thought there was a law against poaching dinosaurs.... maybe just in Australia :goofy:

I'm guessing a pastigauges are similar to feeler gauges only made from plastic. Does that sound right? If so, are they better?

Yes i have heard the assembly lube can cause clutch dramas, was just going to coat it all with oil like u suggested.

Cool guys, anything else?

CrankR.

hehe. Dino oil = class III petroleum vs. a class IV or V synthetic. The synthetic oils and blends are too slippery and don't allow the parts to wear-in properly. You probably can't poach dinosaurs in the states either. ;)

Plastigage is pretty much like a feeler gauge for places that you can't get a feeler gauge into. It looks like a thin string and comes with a width guide to measure the "crush" and give the gap clearance as a result. Each piece is good for a single use, although you usually cut off small pieces and get more than one use from a single string of the stuff.

http://www.hastingsmfg.com/Tools/plastigage.htm

It's a great tool for checking things like journal bearing clearances. The WR/YZ manual includes a step ('07 WR250F, pg5-21/22.4.a-d) to check the camshaft cap clearance before completing the camshaft installation.

no need to buy assembly lube..it is just a way to pre lube everything while the oil is pumped through the engine..just use petroleum based oil.. i think you will need to use a petroleum based oil for the break in..

Hey CrankR, did you buy both hotcams or just one?

If you got both, replace one at a time. you get the cams out by lifting the right side of the cam first, then this gives you enough

room to take the cam chain off. Don't worry about wiring the chain up if you do it this way.

Measure the valve clearances before you take them out.

You most likely won't have to re-shim when going to hotcams.

I don't bother with a torque wrench, there is stuff all room to use one in there anyway. Just nip the bolts up and evenly.

Just follow the manual mate and you can't go wrong. PM me for my number and I will talk you through it if you need help.

Hey crankR, can you please tell me what you think of the hotcams when you get time to ride them? Did they make much difference? worth the money? what area of power gains. I would just like to know on this bike specifically.

thanks in advance.

Yeah Mutu i did buy the Intake cam only. From reading other threads i have learnt that most of the gain is from that cam and the Exhaust cam just compliments it and is not nessesarily needed. Well.... for that reason and because i'm a tight ass :)

The main reason for doing this mod is because i am new to MX (long time trail rider) and don't have the balls to scream around at high revs. This mod is to help lift the 'bottom end' performance as this is the area of the rev range where i spent alot of my time.... for now any way.

I know a pipe will help but the cam change is a cheaper option. Hopefully it will give me enough boost down there.

Will try to get it done this week.

CrankR.

I spoke with a Technician at HotCams the other day. He too suggested using no synthetic motor oil for the first run.

CrankR,

can you give me your impressions on the effort to do the job and how you experienced the difference in performance. I am looking for more bottom end and mid range for my WR - your comments will help my decision making.

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