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Your thoughts on the condition of these valves, piston and cylinder

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I'm in Senegal and picked up this 2002 DRZ400 three years ago. Electrical was a disaster, someone went to town on it which I more or less sorted out (I went through to Reg/Rect). I have no idea what else it has been through but probably wasn't pretty.

I did a leak down test with 70% loss.  I want to get another 3000 - 4000 km (1800 - 2500) miles out of and don't want to put that much into it. Its a backup bike to my CRF450 and XR650.

I thought the cylinder looked ok, could still see some cross-hatching. The piston had some scratching. The valves look pretty bad, some play in the guides

If you had $300 to spend what would you do? I'm heading to MN in a few weeks which will be my only chance to bring back spares.

Thanks.

 

 

P2.jpg

P1.jpg

Cyl 2.jpg

Cyl 1.jpg

v2.jpg

v1.jpg

v3.jpg

v4.jpg

Edited by segge
Added photo

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Where was the leakage from? Rings/valves? Kinda matters in that you can allocate resources to the problem area.

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I could hear air escaping through the tail pipe.

I couldn't measure run out on the valve stems, but there seemed to be a slight lateral play on the intake valves. 

Would it be dumb to replace the valve guides and valves without getting the valve seats cut? I read somewhere that trying to just lap in new valves is a bad idea.

Thank you.

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The valves are are coated. If you lap them you will damage the coating and they will fail premature.

You're not dealing with an old iron bore RM250. You need proper machinist tools to measure and evaluate the condition of the parts. Simply eye balling them is setting yourself​ up for failure.

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Got it...thanks, this is well beyond my knowledge/ability level and that of a local shop.  I'll carry back the head to the US and let a shop do it.

Recommendations for a shop? I'm just into adventure touring, not racing (I'm a 54 year old math teacher), definitely don't need high end.

Thank you.

Edited by segge
more info
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my opinion is if it was sitting for a long time and not even fired, a leakdown test probably didnt tell you jack and it may have been fine .. but send it off to be freshened since its ripped apart now, why not, its peace of mind ..

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The exhaust valves are done for , can easily see the cupping . If you only had very limited $ and for just a cheap fix the head would be where to spend . I just sent 2 heads to Fastheads , have had several done there already and they do good work . At minimal new exhaust valves and the seats cut for them , they could do a light intake cut and reuse your intake valves , this is just with a down-n dirty-just to get by job in mind. Also along this line, a new set of rings and a quick/very light hone of your old cylinder just to put some better hatch marks in for seating the new rings, the plating is hard so it won't as good as with a cast iron sleeve . Would probably keep you in that $300 range and it will get you a couple thousand miles easily , if that's all you want. There may be a few people here that took their oem cylinder out to install a bbkit and it has low miles with the piston that would be better than your well used one.

The correct way obviously is all new valves , seats cut , guides , new cylinder with matching piston/ring kit .

 

.

Edited by jjktmrider

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Intakes look good, exhaust seats are corroding. Pretty typical for an engine that has been sitting for a long time. Cylinder and piston look good. Looks like the PO used the cheapest fuel available which is why there is excess carbon build up and varnish. If it was mine i would have the exhaust seats cut, install new SS valves, reassemble and get liberal with the Marvel Mystery oil to get the carbon and varnish out. YMMV.

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On Saturday, June 10, 2017 at 11:18 AM, segge said:

I could hear air escaping through the tail pipe.

I couldn't measure run out on the valve stems, but there seemed to be a slight lateral play on the intake valves. 

Would it be dumb to replace the valve guides and valves without getting the valve seats cut? I read somewhere that trying to just lap in new valves is a bad idea.

Thank you.

When I got my high mileage DRZ and pulled the head off, it looked identical to yours. Of course the ultimate would be to have the head completely redone and I know the whole "don't lap valves" argument, but I wanted to see if I could make this work for a while.

I bought 2 new Wiseco ex. valves, cleaned all the carbon from cc and valves, lightly lapped in all the valves to see where the seat was riding on the valve face (near the middle) and most of the pits come out of the seat with a light lapping, new valve seals (valve rock was at the max spec.) Measured every thing else and put it back together, been running great for 17,000 kms , valves haven't tightened (checked couple of months ago)

So as far as the head, you may get away with spending little. Piston, bearings, chain i'd be measuring against spec.

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