Honda XR500R-1984 Reviving

[Ivanych]

You're right, the body of the cylinder has been reduced. (this can be seen in the photo).
Mystery revealed!!!!
The aluminium strip has a thickness of 4 mm.

cylinder head of my xr500r is marked MG3 (photos will do later)
cylinder head XR600r (85-87) should be marked MK2 ()
cylinder head XL600r be marked or MG2 ML6 (86-87)
I think the cylinder head meets stock
Correct me if I'm wrong

[Ivanych]

I found a picture of the cylinder and its head.

[Ivanych]

cylinder head! (MG)
What is your opinion about the quality of the middle shaft support?

[Ghost_Mutant]

That center journal looks better than the one off of my top end damaged parts engine:

You can see what the overheating did to the exhaust valve stem seals.
I later determined that the previous owner of this engine swapped position of the banjo bolts for the head/top end oil line. The banjo bolt with the bigger hole goes on the bottom of the oil line

Photo of the other parts engine head that was rebuilt:

Good to know that Honda actually did sell an 84 XR500 that does not have the reed valve. It just so happens that yours is the first I've seen. My heads now have plugs, shown here in this photo.

Regarding the center journal, if you look at the underside of the valve cover, you'll notice that it doesn't have a matching center journal on the XR500. It's been debated as to how much load that cam center journal was supposed to support in the RFVC. Since it doesn't have the matching valve cover half in my engines, I guess it's there to control the flow of oil? Not sure when Honda put the matching half in the valve cover of later XR600s, or if all the XL600s have it.

[Ivanych]

[QUOTE=Ghost_Mutant;15872313]That center journal looks better than the one off of my top end damaged parts engine:

How is it repaired?

[QUOTE=Ghost_Mutant;15872313] I later determined that the previous owner of this engine swapped position of the banjo bolts for the head/top end oil line. The banjo bolt with the bigger hole goes on the bottom of the oil line


If the banjo bolt (2 pieces) have a larger hole, a tube of oil (oil line) remain the standard (unchanged)?
can help the big hole in banjo bolt?
I have had advice from my friend mechanic motor sports (car) of the average prop shaft (center hist). Synthetic oil is high quality - that is his answer.

Ghost_Mutant
I saw your message about the installation of oil pressure sensor.
This is an excellent solution for controlling oil flow in the head CYLINDER.

The question of oil pump:
Can I use a new oil pump № 15100-MN1-771 in return № 15100-MG3-000?

[Ivanych]

Leading the output shaft (23220-MG3-000) has wear and axial play (move, movement)
Than can I replace it? (XR600R, XR650L)
Or should I look for a secondary application in good condition?
Axis motion (backlash) is the norm, or in need of repair.
I ask the council. What do you think?

[Ghost_Mutant]

Originally Posted by Ivanych

QUOTE=Ghost_Mutant: That center journal looks better than the one off of my top end damaged parts engine:

How is it repaired?
To have my bad head repaired, I have to get the center journal welded back up, and then machined back down to proper specification. There are shops here in the US that will do this repair. The damaged head in my photo was not reused. It's actually cheaper to buy a used head without the damage if you can wait for one on eBay.

QUOTE=Ghost_Mutant: I later determined that the previous owner of this engine swapped position of the banjo bolts for the head/top end oil line. The banjo bolt with the bigger hole goes on the bottom of the oil line


If the banjo bolt (2 pieces) have a larger hole, a tube of oil (oil line) remain the standard (unchanged)?
can help the big hole in banjo bolt?
Some people have modified the banjo bolt and drilled out the holes to a larger size. Some other people have suggested that doing this modification will alter the oil flow to the crank in a bad way. After all my research on the RFVC oiling system, I concluded that the stock oiling system works as designed and I don't intend to modify my banjo bolts.

I have had advice from my friend mechanic motor sports (car) of the average prop shaft (center hist). Synthetic oil is high quality - that is his answer.
Many years ago I read a report by an Aircraft mechanic who tested synthetic oils in air cooled piston aircraft engines. He reported that using synthetic oil increased engine wear due to the way the airplanes were used. Because the synthetic is extra slippery, and also since the planes were parked for days at a time, the synthetic oil was draining out of all the bearings while parked. So when the engine was finally started again, there was some extra wear in the engine until the oil pump could recirculate the oil. The solution was to use synthetic blended oils in any engine not equipped with a pre-oiling system. I use blended oils in all my engines and I've been happy with the results.

Ghost_Mutant
I saw your message about the installation of oil pressure sensor.
This is an excellent solution for controlling oil flow in the head CYLINDER.
I think you are referring to my idea of measuring oil flow to the head using a capacitance meter. Initial testing of this idea produced a small effect, but too small to be useful. I have to buy some more materials to try a new test that should increase the sensitivity. I haven't gotten back to that project yet. Other people have different ideas. Search for the Van Pelt oil flow sensor.

The question of oil pump:
Can I use a new oil pump № 15100-MN1-771 in return № 15100-MG3-000?

Yes, I used a pump from the XR600 in my rebuilds, 15100-MY6-670, but the number you listed is the official XR500 replacement oil pump.


Leading the output shaft (23220-MG3-000) has wear and axial play (move, movement)
Than can I replace it? (XR600R, XR650L)
I have some similar wear and play in my output shaft. I decided not to split my case this time. If you don't have a another compelling need to split the case now, the I think you can wait. But if this is your only chance to fix the output shaft, then do it now How far are you going to go, and how much to you want to spend?

The output shaft for the kick start bikes are different from the NX650/XRL. They have the extra section to hold a gear for the kick starter. You need this style of output shaft.

[Ivanych]

Ghost_Mutant!!!!
Thank you for your information and discussion, it is very important to me.


Today I did check the engine, my decision - I will split (disassemble) to identify any shortcomings.
The central gasket is not stock, has many traces of sealant.
There is a leaking oil on the bolts smeary sealant.
I Manufactured a device for convenient work with the engine (it was not enough time, decided to do from the tree).
Sorry forgot to bring a camera, so the only pictures from the phone.

Can I make the change output shaft XR500 (23220-MG3-000) to the output shaft of the XR600R (23220-MN9-641(replaces 23220-MK2-000))????

[Ghost_Mutant]

I just looked at www.cheapcycleparts.com and they only show that countershaft number good back to 1985. For some reason, the 83/84 XL600 and XR500 show discontinued countershafts.

So the obvious question is: what is different from the 83/4 and the 85 up?

I did not separate my cases to replace the countershaft. But I do have a third case that was already split. I also have an XRL and a 88 NX650 transmission that I wanted to use for their 1st gear. So if I have some spare time I can dig this stuff out and compare countershafts for any differences.

I understood that I could swap transmissions from any of the big bore RFVC engines (being aware of the kick start hardware), but I haven't done this yet. I guess now is the time to measure countershafts to be sure that is true.

I may have to wait for the weekend before I'll have time to do this comparison. If anyone else has done a transmission swap into the 83/4 models using parts from 85 and up, please post and let us know about any potential problems.

[a1fa]

In Russia, XR revive you. I am going to bookmark you. Looks like a fun adventure in the making.

[Ghost_Mutant]

I could only find two of the three transmissions I have in the attic last weekend. Didn't have extra time to dig through boxes for my broken 83 XR500 transmission, which is the one I have to find to do this comparison.

I'll try again when I get more free time.

[Ivanych]

Hi Ghost Mutant, Hi guys!
I could not work a lot with the bike this weekend. Was made very little..
Removed the right engine cover and make out the clutch. Discs and the clutch spring in good condition, I am pleased with them.
OUTER COMP, clutch has traces of wear on the friction discs and requires mechanical handling.
Here are photos of my accessories and clutch.

[Ivanych]

Clutch!

[switch]

Someone really abused this fellah... good luck with the rebuild!

[Ivanych]

Originally Posted by switch

Someone really abused this fellah... good luck with the rebuild!

THANK YOU!
I am full of optimism!