The TRX Project: Cylinder head I. Disassembling camshafts & valves..

Hello everyone, one thing that I must to do on my little project is know the status of the headcam that I bought on Ebay. But before that I disassemble the intakes, headcam cover, camshaft caps, camshafts, valves, etc....
Before remove the camshafts I must to ensure the tightening torque of the camshaft caps (10 Nm) and measure the valve clearance using a feeler gauge and take note of the valve clearance of each valve on to a table that I made in Excell and I´ll post soon. This measures must be taked between the valve lifter and the cilindrical surface of the cam, starting with the 0.05 mm sheet and growing up to find the sheet, or combination of them, to find the clearance. The clearance values from the Yamaha service manual are the following... Intake valves 0.15 to 0.20 mm. Exhaust valves 0.25 to 0.30 mm.
To remove the valve lifters with his pads, the valve spings & valves you need a valve spring compressor, like the right image, it´s a Motion Pro tool and cost around 119$ or you can do yourself for less 20$ and some time of work. To build a DIY valve spring compressor I bought a "clamp" (I´m not sure if this is the english name of this tool) in a workshop for around 15$, one cilinder bronze piece, one screw, one nut, two plastic sheets from a bottle of orange drink & some tape. I used a bronze (or aluminium, nylon... ) cilindric piece, this part is from an a keylock that I had in my home but you can do modifying something you have at home like a piece of pipe. To push the valve retainers putting it between the clamp plate and the valve retainer. I cut a part of this piece to extract the valve cotters and the plastic sheets must be between the brass part/pad hole to protect it from accidental scratches. This piece can be done better like the represented in the right sketch, the diameter of the 3 mm socket must be a little bit higher than the diameter of the clamp plate. In this case my clamp plate had 20mm and the socket to seat it had 20.5 mm. In the other side the clamp push the valve foot to his seat, with a rubber sheet and DM part to protect the combustion chamber of marks or scratches. Once the clamp is fitted in the right position, with the axis of the clamp alingned to the valve stem you can turn the screw and compress the spring untit the valve cotters can be removed with the help of little screwdriver or something small enough to remove them. With the cotters out you can turn back the clamp screw and retire the valve retainer, the spring and the valve spring seat. By the other side the valve can be removed. The valve spring had marked the position with blue paint in the valve retainer side, very important to the reassembly of the cylinder head. All the pieces must be classified to be mounted all in the same position becase these parts are subjected to wear and must be fitted in the same place. To do that I did a cardboard box with separators to put all the pieces right classified. To keep all the parts clean and free of corrosion I sprayed all the pieces with WD40 and wrapped with kitchen paper.
HEADCAM CYLINDER HEAD VALVE VALVE SPRING COMPRESSOR DIY VALVE SEAT ENGINE MODIFICATION REPARATION TRX 850 CYLINDER HEAD TDM 850 TDM 900 XTZ 750.

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