Front radiator

Hi all. long ago I read this extraordinary forum of the best bikes ever built family. I have a white VTEC 2009, which I enjoy very much.

As known, the 6 generation gets very hot in town. This is due largely to their lateral radiators.
Does anyone have information on installing front radiators in the VTEC?

Thanks,

Hi and welcome to VFRD!

Vtecs are designed to run Hot so why change it's design. If set up as designed you will have no issues other than seeing High temps on your gauge than you think is normal(but it's not) that mean nothing unless there above 250 deg F.  Vtecs are Lean/ hot running by design, don't worry about it!

Also there is no room for a front rad.

BR

Thanks for the reply. My question was not motivated only by the heat from the bike. The radiator fan spends much time left on, overloading the regulator and the alternator. After many situations as described above, this abnormality causes the breakage of both previously named elements.

Looking through this forum I also found this photo, which shows the possibility of mounting the front radiator and I wanted to know the impressions with its use. Greetings   :smile:
[image: Posted Image]

Looks like it needs oil.

[image: View Post]Monk, on 01 June 2012 - 04:39 PM, said:

Looks like it needs oil.

By the look of the front tire I'm willing to bet it wasn't being ridden at this point and was still in 'project mode'.

[image: View Post]Arri, on 01 June 2012 - 03:52 PM, said:

Thanks for the reply. My question was not motivated only by the heat from the bike. The radiator fan spends much time left on, overloading the regulator and the alternator. After many situations as described above, this abnormality causes the breakage of both previously named elements.

Looking through this forum I also found this photo, which shows the possibility of mounting the front radiator and I wanted to know the impressions with its use. Greetings   :smile:
[image: Posted Image]
Dang!, Is that really the best place for that RR...nestled right next to the hot front bank of cylinders of the bike??!

Beck
95 VFR

[image: View Post]Arri, on 01 June 2012 - 03:52 PM, said:

The radiator fan spends much time left on, overloading the regulator and the alternator. After many situations as described above, this abnormality causes the breakage of both previously named elements.

Actually if I remember correctly that's not true.

I believe its been explained here before that the electrical system on the 6th gen and most motorcycles operatest max output all the time no matter what the load on the system. The unneeded power is dumped off as heat at the R/R. So actually with the fan running that's more power being used and less being dumped back to the R/R to dissipate as heat so it runs cooler there for lasting longer.

[image: View Post]NorthernVFRDave, on 01 June 2012 - 08:01 PM, said:

[image: View Post]Arri, on 01 June 2012 - 03:52 PM, said:

The radiator fan spends much time left on, overloading the regulator and the alternator. After many situations as described above, this abnormality causes the breakage of both previously named elements.

Actually if I remember correctly that's not true.

I believe its been explained here before that the electrical system on the 6th gen and most motorcycles operatest max output all the time no matter what the load on the system. The unneeded power is dumped off as heat at the R/R. So actually with the fan running that's more power being used and less being dumped back to the R/R to dissipate as heat so it runs cooler there for lasting longer.

I would like to know if someone kindly tell me what thread is about the issue that the alternator works in all conditions at 100% load.

I'm sure it can be done, but not cheaply,easily or effectively IMO!  BTW all early and race VFR's,RC's, etc had front rads.
Notice in the posted pic of the front rad set-up you'll notice several things I don't like:
One is oil cooler position! It sits behind not only the rad but behind the headers ramming super heated air into it. :huh:   I want Cooler oil, not hotter!
Also in order to get the needed wheel clearance during compression(not sure if the front wheel/fender won't contract one or both rads under full compression) the lower rad is mounted right on the header which does Not help cooling whatsoever! :ohmy:
I think it's nice fab work, but not sure how well this set-up will function. Not sure if teh stoce bodywork will fit either.

BR

I'm going to agree with BR. That project bike doesn't seem to be helping the cooling situation very much.

The R/r fails because of excessive heat from shunting the unused power. The stock VFR R/r doesn't have an effective heatsink to keep it cool. Partly why when an R/r is on it's last leg, it will start working once you let everything cool off. This is also why some members here just take an R/r with a bigger heatsink off of a different manufacturer and model bike.

 Arri, on 22 June 2012 - 06:45 AM, said:

I would like to know if someone kindly tell me what thread is about the issue that the alternator works in all conditions at 100% load.

I'll see if I can find it, but I beleive the post was a sub topic of another post and I'm sure it was submitted by one of our electrical brains that know the VFR system better than he Honda guys that built the system, so I'm sure he knew what he was talking about.

[image: View Post]Arri, on 22 June 2012 - 06:45 AM, said:

I would like to know if someone kindly tell me what thread is about the issue that the alternator works in all conditions at 100% load.

A PMG (Permanent Magnet Generator) is used.  That means the 'rotor' has a set, fixed magnetic field.  Therefore the AC current produced by the stator is only dependent on speed of the rotor [engine].  To make this ~13.5 v DC, it goes to the Regulator/Rectifier, which rectifies it to DC, and the regulator 'gates' the output to the desired voltage.  Everything else is turned into heat to get rid of.  This is different from a car alternator, which controls the amount of excitation to the rotor.

Benefit:  No brushes.
Disadvantage: lots of heat in an electrical component - reduced reliability.

The pictured bike, is that a naked RC46?  I was wondering if there's a radiator out there that is sort of triangular in shape, one large single rad could be used, with the narrow part near the steering head and have it run downward about to where the front headers exit the head.  Single large fan behind that rad would work.  The setup shown looks pretty messy, are there fans on it?  Why did the oil cooler move to behind the headers, and what of oil filter access?

I don't really care for the stock RC46 rad/fan setup but that thing looks worse to me.

Down here in the sweltering Sunshine State, I've given some casual thought to modding/improving my 5th gen's cooling system, and while I haven't gone so far as to check for needed room/spacing, it seems to me the way to go might be to leave the stock rads in place and (merely) add a smallish 3rd rad (largely) in place of the cross-pipe/hose that connects the 2 OEM rads. I suppose one of these days I'll take a closer look at it.

Biggest problem I see with a front mounted rad, is your now pushing the rad heat back at the motor. A motor that due to design already runs hot. The side mounted rads funnel air in from the from and pushes the hot air out the sides. Same way an Indy or F1 car does.

The extra heat funneling back off the rad could also effect the intake air temperature causing a loss of power or high fuel consumption.

I don't believe there's anything wrong with the theory of a front-mounted radiator--plenty of I4s and other liquid-cooled bikes (and cars) with the same front-radiator configuration; plus, the RC51 race kit features a (more efficient) front-mount radiator in place of the side-mount rads. And the bikes breathe from up above the radiator location (see Honda's CBR600F3 for an example--the ram air snorkel sits immediately above the (front-mounted) radiator--the intake for the VFR and RC51, by comparison, are even further away.)

And, FWIW, Indy and F1 cars have forward-facing radiators mounted in their side pods, not actually side-mounted/facing radiators--their radiators are presented to the airflow exactly like a front-mounted rad, merely mounted either side of the vehicle's centerline.

[image: View Post]south, on 22 June 2012 - 11:31 AM, said:

Down here in the sweltering Sunshine State, I've given some casual thought to modding/improving my 5th gen's cooling system, and while I haven't gone so far as to check for needed room/spacing, it seems to me the way to go might be to leave the stock rads in place and (merely) add a smallish 3rd rad (largely) in place of the cross-pipe/hose that connects the 2 OEM rads. I suppose one of these days I'll take a closer look at it.

All you need to do is slap on two Vtec rads as they are 15% larger(total) than 5th gen rads! RC51 rads are a LOT bigger, but not sure if the piping will work on the VFR though. :ph34r:

BR

[image: View Post]south, on 22 June 2012 - 12:05 PM, said:

I don't believe there's anything wrong with the theory of a front-mounted radiator--

I'm not sure where you got that someone thinks front mount rads are not as good or Better than side mounts? The question was can you fit and will it help to mount Front mount rads on a 6th gen. :rolleyes:

BR

Forgot to add NOT, that's what I ment to type. :rolleyes:

I think almost all of the 'overheating issues' on this forum are 100% mental.  If Honda put a bar graph, or old style analog meter with 'C' and 'H', and 200 degrees was right in the middle, you wouldn't be hearing much talk about cooling here.  Has anyone here actually experience an overheating condition that was due to the design of the bike (vice punctures, leaks, etc)? Having a digital readout that says "220" seams really bad, but really, it's working just fine.  And the fan running is part of the design as well.  If the fan starts, and temps go down, then everything is great.  Heck, my Triumph's fan comes on while easily riding through town at 35mph in 45 degree weather.

Due to the V4 engine's front bank sticking out forward, for Honda to fit a front mount on our bikes, they would have to either increase the wheel span, or rake of the front wheel.  Both of which are negative to handling.  Thankfully they picked the side mounts.

In my mind, if it ain't broke, don't fix it.

Excellent question Arri.

Welcome aboard...

Many would say that this bike was not meant for riding around town... it's a sport-tourer...

But the truth is on a hot day on speedy up-hill runs when your pushing the bike hard, it will overheat...

Heat is the enemy of any electrical system and all electrical components. Actually not just electrical components but almost all components. The fresher it runs the longer life all components will enjoy. There is nothing wrong with wanting the bike to run cooler... I believe it would be an admirable acheivement.

A larger oil cooler is perfectly possible and will help to a degree. I believe the SP1's oil cooler will fit on the VTEC and is larger.

If the header pipes didn't jut out so far forward there might just be some space in there for some sort of 3rd radiator... but perhaps the headers are required to hace that length of straight pipe on leaving the motor due to lambda waves or whatever they are...

Then there's the direction of flow created by the fan when it comes on and the bike is in forward motion... which cancels its effectiveness completely and doesn't help...

This topic has never really been resolved....

[image: View Post]Baileyrock, on 22 June 2012 - 02:48 PM, said:

[image: View Post]south, on 22 June 2012 - 12:05 PM, said:

I don't believe there's anything wrong with the theory of a front-mounted radiator--

I'm not sure where you got that someone thinks front mount rads are as good or Better than side mounts? The question was can you fit and will it help to mount Front mount rads on a 6th gen. :rolleyes:

BR

You may answer your own question if you'd care to un-roll your eyes long enough to direct your attention to the post by NorthernVFRDave immediately above mine: wherein NVD voices his concerns that a front mount rad results in a(n undesireable) hot air stream directly back on the motor, and where "extra heat funneling back off the rad could also effect the intake air temperature causing a loss of power or high fuel consumption", and going on to state that (high tech) Indy and F1 cars opt for side-mount rads over front mounts.

My comment was/is merely that his concerns with front-mount radiators were/are unfounded, ergo a front-mount rad should function every bit as effectively on a VFR as on anything else.

[image: View Post]Arri, on 01 June 2012 - 03:52 PM, said:

[image: Posted Image]


More HERE:  http://www.motor-for...00-v-tec-1.html


He also removed the VTEC (16 valves all the time, different valves), bored it to 836cc JE pistons....



last pic from the thread

[image: Posted Image]

 Dutchy, on 24 June 2012 - 08:27 AM, said:

[image: Posted Image]

Ducati looks without the high maintaince cost LOL.

Not to really stir things up, but for some reason I think in most cases the Honda engineer that designed the VFR's cooling system knows a lot more about thermal dynamics than all of us put together. If a front mounted rad would have worked on later model VFRs they would have done it. At some point in time during the life cycle of the VFR it became a need to move away from the front mounted rad to side mounted.

I have mine with the thermostat stuck open and runs cool  70-73c on a run on the highway and 90 in town idle traffic .I had to replace the plugs as it is running way too rich fouling all 4 plugs which here are not cheap,clean air filter and good injector pattern as I cleaned them at work . So cooler is not actually better all the time .

Someone used to make an auxiliary radiator for the RC51 which mounted in the front, between the OE side mounted rads. You would chop the crossover hose between the two side rads and splice the aux rad Inbetween.

But it's not made anymore.

This part was separate and distinct from the HRC front mount rads that you would have found on Nicky or Colin's racebikes.

I wanna say it was a Moriwaki piece, if my mind serves me correctly.

If one could locate such an item, it might just fit on a VFR perhaps.

If the thermostat is functioning correctly, the bike wouldn't run below about 82 degrees C, despite the additional rad.

This whole "you don't want hot air coming off a rad and towards the motor" thing is kind of nutty when you think about the cars that most of us own doing exactly that.  Or the fact that the left hand rad on an RC46 does this same thing already as long as the bike isn't moving (if it is moving, air stagnates there).

If the RC51 ditched side rads for fronts on the race bike, and we look at the modified RC46 in these pictures, I think we could probably assume that the rads are on the side of packaging and ease of maintenance vs. outright performance.  Race mechanics are probably better at dealing with these issues vs. the average shop monkey or owner who does his own work (like me).

My theory is that a single large radiator with a thick core and a good fan and fan shroud mounted up front will do an excellent job cooling these bikes.  The problem is that the front of the engine where things like the oil filter live may be harder to get to.  Without a custom rad with a peak starting near the steering head it will be hard to test this theory and I'm not about to try to learn how to build a copper radiator at home but that might be the answer.

If a guy has cooling issues I think the best route is making sure the block and rads are flushed yearly, and I mean using a hose directly on the block in both directions of flow so this could be an all day party, then get the VTR fan blade mod, and then the 205F rad fan switch in place of the 220F unit that the factory installs.  As long as the fans are functioning well and the rad and block are clean and the water pump is doing its thing well then you should be in tall cotton.  The sad thing is, this really looks horrible if someone wants a naked RC46 but that's another issue for another time.

[image: View Post]CrazyT, on 22 June 2012 - 03:09 PM, said:

I think almost all of the 'overheating issues' on this forum are 100% mental.  If Honda put a bar graph, or old style analog meter with 'C' and 'H', and 200 degrees was right in the middle, you wouldn't be hearing much talk about cooling here.  Has anyone here actually experience an overheating condition that was due to the design of the bike (vice punctures, leaks, etc)? Having a digital readout that says "220" seams really bad, but really, it's working just fine.  And the fan running is part of the design as well.  If the fan starts, and temps go down, then everything is great.  Heck, my Triumph's fan comes on while easily riding through town at 35mph in 45 degree weather.

Due to the V4 engine's front bank sticking out forward, for Honda to fit a front mount on our bikes, they would have to either increase the wheel span, or rake of the front wheel.  Both of which are negative to handling.  Thankfully they picked the side mounts.

In my mind, if it ain't broke, don't fix it.

I got stuck in stop and go traffic in 95 degree weather and after about 30 mins my bike overheated.

[image: View Post]Baileyrock, on 22 June 2012 - 02:46 PM, said:

[image: View Post]south, on 22 June 2012 - 11:31 AM, said:

Down here in the sweltering Sunshine State, I've given some casual thought to modding/improving my 5th gen's cooling system, and while I haven't gone so far as to check for needed room/spacing, it seems to me the way to go might be to leave the stock rads in place and (merely) add a smallish 3rd rad (largely) in place of the cross-pipe/hose that connects the 2 OEM rads. I suppose one of these days I'll take a closer look at it.

All you need to do is slap on two Vtec rads as they are 15% larger than 5th gen rads!
BR

I've been curious about this, has anybody done the 6th rad swap to a 5th gen? Doesnt seem like it would be that hard.

I thought about it. Didn't get around to it.

For the Torocharger install on a 6th gen, the RH radiator is replaced with a 5th gen unit for clearance.

When the Vtec first came out in 2002, Hondas ad copy said the rads were 8% larger, FWIW.

[image: View Post]south, on 22 June 2012 - 05:26 PM, said:

[image: View Post]Baileyrock, on 22 June 2012 - 02:48 PM, said:

[image: View Post]south, on 22 June 2012 - 12:05 PM, said:

I don't believe there's anything wrong with the theory of a front-mounted radiator--

I'm not sure where you got that someone thinks front mount rads are as good or Better than side mounts? The question was can you fit and will it help to mount Front mount rads on a 6th gen. :rolleyes:

BR

You may answer your own question if you'd care to un-roll your eyes long enough to direct your attention to the post by NorthernVFRDave immediately above mine: wherein NVD voices his concerns that a front mount rad results in a(n undesireable) hot air stream directly back on the motor, and where "extra heat funneling back off the rad could also effect the intake air temperature causing a loss of power or high fuel consumption", and going on to state that (high tech) Indy and F1 cars opt for side-mount rads over front mounts.

My comment was/is merely that his concerns with front-mount radiators were/are unfounded, ergo a front-mount rad should function every bit as effectively on a VFR as on anything else.

WHAT???   :huh: