5th Gen VFR800 Oil Cooler Swap

I had considered such a mod in the past, the consensus after much research and discussion with people who deal with these types of things was that the benefit wasn't worth the effort. It is my belief that the minimal increase in volume of the two different oil coolers isn't really going to do much of anything, positively, or negatively. A deeper oil sump with a higher volume is going to accomplish more than adding a couple drinking straws worth of volume to the cooler. Not that I'm bashing the mod, I say do it if it's gonna let you sleep better at night.

 

http://vfrworld.com/forums/mechanics-garage/31677-rc51-oil-cooler-5th-gen-how-pics.html

 

I don't think it would make much difference. The same oil pump is used on the CB900F, CB1100F, CB1100R, with the 1100R having an oil cooler abour three times the size of the 900F. The 1100s are not noted for lack of oil pressure.
This is an interesting topic for me as I am looking to put an oil cooler on my 84 VF1000RE, I have the dual chamber pump and modified sump already.

 

Sorry about the late reply. I just thought that the RC 51 oil cooler might hang down lower than the original. Not sure if it would interfere or not, but it sure would be worth checking.

 

Yes I am intentionally resurrecting this thread.

Tink - A while back you were considering trying to compare temps with another bike. But that was in the run up to last winter, so I guess it never happened. Now temps are finally picking up, I wondered if you have had a chance to set this up, and if so what did you find? I guess if you could head out on a longish run in hot conditions, with an otherwise similar 5th gen, it should quickly confirm what impact the bigger oil cooler has, especially on the peak temps.



SkiMad

 

So that'll be a no then... :smile:

In the mountains this side of the pond, we had a great ski season and were still skiing at the end of April. Since then it warmed up and we had two days of intense rain, and overnight quiet streams have turned into raging torrents rushing a trillion snowflakes down to Lake Geneva. Already most of the major Alpine road passes are now OK on a motorbike but there is still heaps of snow stacked at the sides, with run-off creating sheet ice overnight to catch the unwary.

Anyway hopefully it won't be too long before you too can enjoy the sound of a VFR storming up a mountain valley :whoo: and we can all find out whether it helps a VFR keep its cool when you fit a much bigger oil cooler!

Take care



SkiMad

 

The main difference you will see is quicker cool off when taking off from sitting still. I still havent installed a fan to help cool off while sitting. Summer wise here while at highway speeds its about the same, maybe a tad cooler. Winter I have to block it off when on the highway a good ways. If in town then I unblock or partial block. These engines have no problem heating up when idling.

What is your temp, altitude, humidity, etc where you are right now skimad?

 

If you believe my iPhone, then its only 12 degrees C and 85% humid and I am at just over 1,220 metres above sea level (roughly 4,000 feet). The lowest point around here is Lake Geneva at 370 metres (1,200 feet), but there are plenty of mountain passes in the vicinity which top well over 1,700 metres (over 5,500 feet).

Like others I have seen some very hot temps on the VFR especially during mid summer. But the issue I am trying to resolve is finding a way to have the bike warm up and run normally but be better able to dump excess heat at low speed when the engine is working really hard. We don't really have traffic jams ever around here - stop start traffic is for cities! I live in a ski resort in the Alps on the Morgins pass linking France and Switzerland - where those steep climbs just go on and on, and in mid summer the fan is running full chat all the way to the top and much of the descent too as hairpin turn after hairpin turn never allows the bike to pick up enough speed to dump the heat unaided.

As I am not worried about traffic jams - the VTR - reverse fan blade makes a lot of sense as it works with, rather than against the natural air flow. However even that fix struggles to dump enough heat especially during an enthusiastic blast. Sitting on a volcano can be pretty uncomfortable. Down side of underseat exhausts!

That is why I am very interested to see how Tinks oil cooler mod works out..


SkiMad

 

I ride in 100+ temps and have had this cooler on awhile now. It only hepls so much. Tye cooling system is just not a good setup for non racing. When coolant is bypassing the rad with the fan then it can only do so much.

What would help more is air channels for the rads and probably bigger rads. Inlines get a nice big rad up front and we get two small rads on tge side.

 

"The VFR800 has two oil pumps in the same assembly. One side of the pump feeds the oil cooler and the cooled oil goes to the transmission gears (chapter 4 of the factory service manual)."

Hey Tinks, you got that wrong. Both pumps collect oil via a common oil strainer & pickup gallery, then the HP one feeds the oil filter & all bearings loads, including the gearbox. The LP one feeds the cooler to cool the oil & then returns it to the oil pickup gallery at the HP inlet, thus diluting the oil feed to the HP side with cooler oil ! So it IS cooling the bearings !

The 5th gen manual does not show it well as they included the gearbox shafts on the picture, but if you look at the sump, you can see that the return line from the cooler comes in the left side & through an internal gallery to the oil pump body. You can see it better in the 6th gen manual which has been laid out in 2D.

 

Yea, a temp gauge would be nice. You could install a temp controlled valve so youre not over cooling. I emailed Toro years ago if ye would sell his oil like connections so we could could use soft lines and do stuff like this, but he never got back to me. I dont even know if hes still making supercharger kits anymore.

 

The larger cooler is always going to give a lower oil temperature, which provided it's not frigid, is always better for the bearings which create their own & aborb heat from the attached components, so chilling your oil is always going to help keep the engine internals from wearing or over heating.

Image below from 6th gen manual shows where the oil returns, on the 5th gen manual you have to blow it up & look carefully to see it is the same !

Re temp check, I have a remote temp probe gauge, that I could rig up temporarily to record temp into the cooler & temp out of the cooler. Just need to remember where I left it & wait a couple of weeks as I'm off to the Northwest 200 road races in Northern ireland on Wednesday