I had one free day and I spent it with my bike. This day was difficult for me. I checked Cylindercompression. It was hard. 30 minutes of jumping but the device showed only 8 kg / cm 2, it is not enough. I am very upset. I took the engine out of the frame (it was easy to do) and opened it. When I saw the engine in, I became very angry !!!!!! I want to tear hands mechanics, who collected the engine in front of me. It's horrible, it wanted to kill this engine !!!!! 1. Part of the fastener head cover, cylinder head and lost and replaced by strangers. I'm surprised! Where native bolts (hardware)?? 2. Single bolt cylinder head was not screwed in (only by hand). The mechanic had no memory?? Mounting bolt cylinder is shortened. Why?? 3. Everywhere (everywhere) snot on the sealant. 3. The ends of the release valves were shortened ?????? 4. ARM EX.SUB ROCK - has a great point wear !!!!! (A bad valve adjustment!) 5. Chain tensioner received many blows with a hammer !!!!! 6.Piston and the cylinder has a large scratches, but the rings are good. Why?? Small gap between the piston and the cylinder (the error in grinding??)?? or is it mud sand) in the assembly?? 7. Piston clean without soot but has traces of blow valves! Who can identify this piston? This WISECO?? Now I am left to disassemble the cylinder head and I'll have a lot of questions in this forum that I should do next. [FONT="] [/FONT]
I'm sorry to read about the condition of your engine. I never liked opening things up and seeing this type of work. It looks like you need to replace a bunch of parts. I purchased some new stainless steel valves from a guy in Israel to fix up my spare head: http://cgi.ebay.com/ebaymotors/HOND...wItemQQhashZitem33665e1ed8QQitemZ220760776408 These were the cheapest I've found, but I haven't used them yet. My XR500s currently have Kibble White Black diamond valves. I don't know what kind of piston you have. Except for the valves and gaskets, I used Honda OEM parts in my rebuilds. You should measure the cylinder bore to see if it really is 92.5mm. I don't understand why your engine needed the spacer between the case and cylinder. Perhaps you should look at the crank to be sure it's the stock XR500 assembly with the 75mm stroke. I couldn't afford to replace all the parts you need in my rebuilds with new. Perhaps now is the time to look for a donor engine, but I understand these machines are hard to find in your location.
I think I need to replace the piston, cylinder, and have a lot of new parts for the cylinder head. I want to get displancement - 600ss in my engine with the repairs. (if possible) Can I use parts (cylinder, piston, crankshaft, BALANCER) of XL600 or XR600R85-87 with CRANKCASE and cylinder head on my bike XR500R? How can I get displancement = 600ss in my engine? Which ideas are the professionals?
If I wanted to make my RFVC 500 into a 600, I would just buy another engine from a XL600 which I think will swap in using the existing brackets. The XL600 has the same 75mm stroke but with a larger 100mm cylinder bore. However, the newer XR600 cylinder is taller, and I think custom brackets for the valve cover upper engine mount might be needed to fit into the 500 frame. But I'm not 100% sure of that. Someone has probably done this swap before. If you could find such a 600 engine in good condition, that is usually the cheapest way. I don't think I would spend money to buy the XL600 parts separately. Most of the dealer prices I see are too high for my bike building budgets to do that kind of swapping. Only you know what prices are like in your location. It would be cheaper around here to just buy another bike But part swapping to make a 500 into a 600 is possible if you were willing to track down all the differences. The 500 has a different clutch basket than the 600. The buffer springs in the 500 basket are slightly weaker. Also, the primary drive gear on the crank is different between the two engines. Or I should say it is on my 84 XR500R........... but I'm not sure about your XR500.
I was just wondering, when you were checking compression, did you disable the decompression valve and hold the throttle wide open. That would make a difference I would think. Also, the piston appears to be at least 11 or 12 to 1 considering the dome and relief pockets for the valves. You should have way better compression than what you mentioned.
Riddle of the appearance of an aluminum strip under my engine cylinder is solved !!!!! This is a high piston !!!!! He does not fit in the cylinder!! :eek1 I don `t know who came up to put it into the motor. This is a photo without the aluminum gasket. (post # 19)
Yes that is a Wiseco piston, apparently not the right one for the application. But appearances can be deceiving. Run the numbers to verify. Pray it is the wrong piston. The grinding on the valve stems suggest that there was no more adjustment left in the tappet so they ground it down to "create" adjustment? Scary stuff. You run out of adjustment as the valve wears into the valve seat. Running out of adjustment is your final warning before the motor drops a valve. You need to pull the crank out because if the Wiseco piston is correct for that motor, then the connecting rod is not. Sean
I'm guessing that the crank is not stock, and therefore the stroke is not 75mm. Check the case serial number to determine if the bottom end is from a more recent Honda XR with 80mm stroke. If I recall correctly, all the big bore RFVC engines have the same length connecting rod. Somebody please correct me if I'm wrong on that one.
hi! Mystique continues! I spent the measure: stroke = 75 mm piston pin = Ф 22 mm. This KRANKSHAFT belongs XR500R (I think so) What is the height of the body CYLINDERS? (height shirts?)
