Is it possible/practicle to fit an oil cooler to a lc4 640? thinking being that this would allow greater distance between each service or am i being a numpty?
With decent quality oil, the microscopic debris that are too small to be filtered out by the oil filter is more reason for an oil change than oil breakdown. If you aren't seeing high oil temperatures, it may be more trouble than it is worth (parts cost, oil leaks, vulnerability). Do you have external oil lines? If so, it wouldn't be too difficult to add a cooler. Some of the aftermarket companies make shields for them, too. They are ususally bike specific for BMW models, but could be modified to fit I'm sure.
LC4 has plenty of capacity without a cooler for a "non-race" application. It's Dakar proven, repeatedly. Loved mine, but it's not practical in N. Texas. Too far to good dirt roads, and not enough snot to run 80 across Dallas to get to OK. Had to swap to the 525/950 combo I do have one on my 525 though
Yer being a numpty. Your 640 already has an oil cooler - the front frame tube. This gives the extra capacity & cooling that other people have to spend $$$ on aftermarket bling to get. Cheers Clint
a lot of bikes have front oil frame tubes doesnt imply the bike doesnt need an oil cooler, us xr600 folks have the same type of oil frame and need on occasions an oil cooler...same for the xrl folks to honestly give a yes or no you need to get an oil thermomemeter if you ride above 250-275f oil temps ALL the time then you could probably benefit from a cooler, or improve the watercooling, air flow to engine, etc... 300f is the critical oil temp you want to avoid you can do some experimenting and then decide on a yes or no
You are right, maybe for extreme conditions it could be a help, they do run an oil cooler on the rallye bikes after all. Maybe get one of those nifty wee oil fill cap thermometers & see what she runs at. I'd be spending time & money on a 2nd radiator fan first before worrying about that though. Cheers Clint
Most bikes that run an oil cooler are air cooled, like the DR650, DRZ250, XR400, old school GSX and GSX/R and GS series, etc. Not all air cooled bikes come with a factory oil cooler, but most liquid cooled bikes do not come with an oil cooler.
The LC4 rally bikes had an oil cooler, both the 660 and the 690. The 660 had an external line. The 690 is more integrated solution. ] So in extreme case it is useful. However, oil cooler can make the engine run too cold. You should use bypass valve on it.
