not a 500, but big bore and long stroke
For quite a while, exposed valvetrains were commonplace in aircraft engines. The mechanic would oil up everything before take off, and off ya' go.......
As for the rod bearing issue.... the rods are not lubricated by "oil pressure" as most people think.
Oil gets pumped into the crankshaft, and centrifugal force takes it from there.
You might have 50 psi at the mains, and the equivalent of 120psi at the rods at high rpm due to centrifugal force.
The rod bearing in the CR500 is the hardest thing to lube... as oil is constantly being flung off of it...
- dannygraves
- Posts: 8020
- Joined: June 1st, 2007, 2:03 pm
- Location: Las Vegas, NV
if there isn't enough pressure to get to the valvetrain, then there isn't enough to come out an oil sprayer, the oil sprayers have a little ball and spring assembly to only allow them to spray at over a set psi (mitsubishi is 20psi, for their turbo motors that have sprayers)
'09 kx450f 4-Poke
Gen-4 trail bike --SOLD--
Gen-3 badass trail/mx bike --SOLD--
Gen-1 built dunes bike --SOLD--
'05 klx110 --SOLD--
'95 pw80
Gen-4 trail bike --SOLD--
Gen-3 badass trail/mx bike --SOLD--
Gen-1 built dunes bike --SOLD--
'05 klx110 --SOLD--
'95 pw80
There is no such thing in the sprayers on any dirt bike ive ever worked on. Its basically the same plumbing as a leak jet setup on the accelerator pump. According to physics, fluids always take the path of least resistance which means most of that tiny amount of oil thats left gets pumped right back where it started via the squirter. Im guessing since most thumpers have roller rod bearings that any type of spring/bearing setup would just cause too much oil to be diverted through the rod bearing instead of "squirted" onto the piston?
Faster then Speedy Gonzalez, slower then the Road Runner!!! MEEP MEEP
2002 CR80
1999 Cr500
2003 CR250R
2005 CRF250R
2006 YZ450F
2005 CBR1000RR
1997 Banshee
2002 CR80
1999 Cr500
2003 CR250R
2005 CRF250R
2006 YZ450F
2005 CBR1000RR
1997 Banshee
- Roostius_Maximus
- Site Admin
- Posts: 4641
- Joined: November 16th, 2007, 3:24 pm
- Location: Mt Nebo, Manitoba, Canada
- Contact:
a drysump stil has to scavenge the oil, if theres a hole in any part of the engine it will draw from the easiest source. like trying to suck chocolate milk up a straw with a hole.
In our stock car engines we run so much negative pressure we have a regulator to vent atmosphere into the crankcase. we run enough vaccum to seal the rings tighter, but trim it so it wont suck the crank seals or gaskets in. We also have to run a pop-off so when my guy comes into the corner at 9800 and stuffs the brake the engine drops about 4000 rpm and goes into positive pressure.
In our stock car engines we run so much negative pressure we have a regulator to vent atmosphere into the crankcase. we run enough vaccum to seal the rings tighter, but trim it so it wont suck the crank seals or gaskets in. We also have to run a pop-off so when my guy comes into the corner at 9800 and stuffs the brake the engine drops about 4000 rpm and goes into positive pressure.
http://www.youtube.com/user/500bigbore
My CR500 Tech Reference... http://sdrv.ms/1a0CIiz
MRE Components... http://sdrv.ms/1bs2zhd
My CR500 Tech Reference... http://sdrv.ms/1a0CIiz
MRE Components... http://sdrv.ms/1bs2zhd
Roosty, on the Yami thumper I own, they have seperate scavenge and pressure sides. The scavenge pulls from the bottom of the case and pumps to the oil resevoir only. Then the pressure takes it where it needs to go. On the Hondas, they are wet sump, so a short cicuit is just as bad...
Faster then Speedy Gonzalez, slower then the Road Runner!!! MEEP MEEP
2002 CR80
1999 Cr500
2003 CR250R
2005 CRF250R
2006 YZ450F
2005 CBR1000RR
1997 Banshee
2002 CR80
1999 Cr500
2003 CR250R
2005 CRF250R
2006 YZ450F
2005 CBR1000RR
1997 Banshee
- Roostius_Maximus
- Site Admin
- Posts: 4641
- Joined: November 16th, 2007, 3:24 pm
- Location: Mt Nebo, Manitoba, Canada
- Contact:
ya, same thing like we use, 3 sections of scavage and 1 section of pressure. common for us is the scp-204-a
http://pumps.scpdrysumps.com/
routed something like this....
we'll usually mount the krc power steering pump on the back of it, and sometimes spud an enderle fuel pump to that yet too
http://pumps.scpdrysumps.com/
routed something like this....
we'll usually mount the krc power steering pump on the back of it, and sometimes spud an enderle fuel pump to that yet too
http://www.youtube.com/user/500bigbore
My CR500 Tech Reference... http://sdrv.ms/1a0CIiz
MRE Components... http://sdrv.ms/1bs2zhd
My CR500 Tech Reference... http://sdrv.ms/1a0CIiz
MRE Components... http://sdrv.ms/1bs2zhd
That drawing is hilarious! It depicts a motor with huge velocity stacks and dry sump (exotic) oiling and then they put some stock looking exhaust "manifolds"...HAHAHA
Faster then Speedy Gonzalez, slower then the Road Runner!!! MEEP MEEP
2002 CR80
1999 Cr500
2003 CR250R
2005 CRF250R
2006 YZ450F
2005 CBR1000RR
1997 Banshee
2002 CR80
1999 Cr500
2003 CR250R
2005 CRF250R
2006 YZ450F
2005 CBR1000RR
1997 Banshee
- Roostius_Maximus
- Site Admin
- Posts: 4641
- Joined: November 16th, 2007, 3:24 pm
- Location: Mt Nebo, Manitoba, Canada
- Contact:
ya,
http://www.youtube.com/user/500bigbore
My CR500 Tech Reference... http://sdrv.ms/1a0CIiz
MRE Components... http://sdrv.ms/1bs2zhd
My CR500 Tech Reference... http://sdrv.ms/1a0CIiz
MRE Components... http://sdrv.ms/1bs2zhd
- dannygraves
- Posts: 8020
- Joined: June 1st, 2007, 2:03 pm
- Location: Las Vegas, NV