you sure you don't have air in the system? An air bubble would screw you up pretty good?

 

Not positive that I don't, but I spent a bit of time smacking hoses with a screwdriver and blipping the throttle to make sure I didn't. But yeah, air in the system isn't fully ruled out yet. Especially since I have all that hose re-routing and such. I may do a system flush and another round of working the air out. It's not like I wasn't really expecting to need to work out some kinks here and there...

 

Find yourself an infra red thermometer and check actual radiator temp.
Mine ran anywhere from 208 to 194 during normal operation, as did the temp gauge.
I was using a 929 gauge cluster with the stock temp sender from the VTR thermostat housing.
In the five years I owned the bike it only reached 250's while running at a 100 plus in 100 plus temps for an extended period of time. Once I installed the second fan the bike actually ran cooler than stock VTRs/VFRs/RC51s.
Also, while you're trying to figure out your cooling system, I'd run distilled water instead of coolant, it's cheaper and not near as slippery when it gets on the rear tire.
As a matter of a fact that's all I ran for the 5 years I owned the bike.
Make sure that all the air is out of the system. I used a shrader valve in the right upper rear of the radiator to allow bleeding of the system.
Take a look at the coolant flow diagram in the service manual and make sure that you have the same flow pattern.
Hot water should come in at the top of the radiator with the cooled water coming out the bottom to the pump.
If you're using stock VTR fan blades be aware that they are pushers and need to push air through the radiator towards the tire. If you're using something other than those they will not be near as efficient as the stock blades in pushing air through.
I did try sucker fans, i.e. pulling air from the tire area up through the radiator to under the seat but the engine ran much hotter that way.

Any questions, let me know.

 

Kai Ju- thanks for the advice.

I actually have a Shrader valve as per our phone conversation like four months ago. The thing works great! No leakage, and I can release all the air from the system. I can take more detailed pics, but studied up on your setup pretty well when I was installing mine. Hot water from the thermostat is routed alllllllll the way to the radiator cap in the back, and the cold water goes back to the pump. Every time I was buying/fitting hoses I got into a confusion and double checked the flow diagram again. I must have checked 10 times (11 now because you got me worried again!)

The major difference is that I have one puller fan and one pusher fan (the stock VTR one) on the rads. I aligned them so that the pusher is at the lower end of the rad (and in the seat compartment) and the puller is at the upper end (and on the tire side), so that most of the square surface is covered with some kind of air being forced over it. Using my hands, it seems to be working well, but that's just using my hands.

I suspect my temp reading problem stems to an electrical issue.

Infared Temp Gauge= New Toy. This is something that I didn't consider and will probably save me a bit of headache.
I will get some distilled water tomorrow, I should do a flush anyway...

But again, thanks for posting your bike and taking the time to talk to me, I still have the notes from before and wouldn't have know where to start without them (other than to buy a VTX radiator).

On question... about how long did it take for your fan to kick in in an average day (say, 80 degrees and medium stress riding)? I'm just trying to get an idea of what I should expect so I know when to start adjusting things...

 

Depending on ambient temp my fan would come on within about 15 min of riding, when the water temp reached 207 F, the fan would bring the temp down to 194 F and turn off. Once the cooling system reached the initial fan on temp it would continue to cycle as long as I was riding. The only time the fan didn't come on was when i was riding in the rain and the radiator became watercooled. As a matter of fact on rainy days the temp would not go over mid 150's, i.e. thermostat opening temp.

If you want to run the puller fan, consider running it below the radiator. Either directly below the pusher or where you have it now but between the tire and the radiator. make sure you have enough room though.

BTW, I used the rear cowl rear mounts to hold the rear of the radiator with straps running from the radiator to the cowl mount. make sure they are properly rubber mounted.
In the front I used angle aluminum that was attached to the front of the radiator using rubber grommets and sleeves and attached to the subframe with RivNuts. I had to make a cut out for the radiator discharge pipe.
Also, make sure that the radiator is grounded or the fanswitch will not work since it's a single wire switch. It grounds through it's body to the radiator to the frame. Any of those not working will prevent the fan switch from working.

Here is the link to my thread that shows the front mount:
https://www.superhawkforum.com/forum...r-image020-jpg

and here is a pic of the rear mounts. IIRC I used the fairing stays to make those brackets.
https://www.superhawkforum.com/forum...r-image027-jpg

If you go to post #89 there are several pics showing more details of the plumbing such as the thermostat housing with the lid reversed as well as the rear mount and the plumbing along the left side of the subframe and at the water pump.

Keep the questions coming.

 

Yep, the puller fan is below the rad, offset from the other fan (so that between the two of them they cover a big majority of the radiator). I made sure to not allow my tire hugger to hit the fan (I have raised the tail a bit anyway). I actually think that I'm all set as far as your conversion goes.

This is the pic of the Shrader valve and you can also see the wire ties I used to secure the rear. There is rubber foam padding in between the radiator and fram, which you can also see. I also grounded the radiator to the frame with 12 gauge wire just to be sure


This is the puller fan, placed near the upper part of the rear radiator. It's off a gixxer and pulls a good deal of air- I can feel the heat just blowing down.


And this is the pusher fan, located near the bottom of the rad.


Everything is rubber mounted and seems to be flowing well. The rads get hot, and fans blow that hot air right onto my tire hugger.

What I am (still) troubleshooting are two things...
1) The fans don't kick on when the radiators get hot. I have a fan switch wired in, but this is just temporary so I can diagnose one problem at a time and make sure the fans work (they do!)

2)My gauges are not reading an accurate temperature. I get a flashing 270 degrees as soon as I turn the key (max) and haven't figured out why.

What I have done/checked:
-Thermostat opens up at the correct temperature.
-System has been properly flushed.
-I replaced the thermosensor that sends signals to the gauges. It's used as well, but I get the exact same readings so I don't think this is the issue.
-There MAY be something to cause oil to be in the coolant. My first round of flushing I saw oil in the coolant, but it could have been from the rebuild. The oil in the bike is not milky, there was very little in the coolant, and I haven't seen it since. I have temporarily ruled this one out...

-Here's a big one, and a funny story: Car wash solution is the same color of coolant. So I put soap in my radiator by accident. It only ran like that for about 10 minutes, but the damage was done and I spent a good part of an hour flushing it out by running a hose into it, then distilled water. I emptied it out and refilled several times. This may have been a bad idea but seemed to work.

There are a lot of indicators here, I think that I weeded through them and fixed all the mechanical ones, just haven't figured out the gauge quandry.

I am looking into gettting an infared thermometer in the near future...

 

You did have the clutch cover off, correct? If so that is when you got a little bit of oil in the water pump. No big deal, check the oil for coolant but don't worry too much about it.

 

Oh and car wash soap.......

 

Affirmative on the cover being off and affirmative on the no coolant in the oil- and there was just a little oil. Nothing that seemed to be a problem, I just wanted to point it out in case it may be linked to my other issues.

And the car wash was pretty funny. Turns out that a water pump is a suds frothing machine!

I ended up putting a running water hose in the radiator cap hole and removing hoses from the water pump, putting them back on, blipping the throttle a few times, and repeating. It seemed like it would never end, but after about 30 minutes, the whole system had crystal clear water pouring out, and finished it off with a nice round of distilled water.

I may have to hunt Tweety and his threads down down to see if he had issues with his gauges...

 

But that's good to know about the coolant... clutch cover off= some oil may have gotten in

 

If you're using an F4i gauge cluster, you have to use a compatible temp sender.
Like I said before, the fan switch is mounted to the radiator and will not work unless it's grounded.

Regarding the soap, you now have a really clean cooling system.
Also, soap breakes down surface tension in water and this might actually make it more effective.

 

You guys really ougth to try an old classic...

It took me all of 30 seconds to verify that an F4i and VTR have entirely different values on their termosensor... So it's really no wonder that you get those values... Swap in F4i sensor...

 

I tried to tell him that in my two previous posts.
I had that issue when I installed the '07 CBR600RR gauge cluster on my CB-1.5 and got some odd readings. When using an FI system sensor it's helpful to remember that one wire goes to the gauge while the other one goes to the ECM.....

 

Haha, I was listening, guys. Actually, Lazn mentioned a little while back...

I'm going to try an f4i sensor. Problem is, the part number for the F4i sensor is the same for basically every water cooled Honda four stroke ever made.

That is why I was/am tentative about doing this. I already swapped the sensor once, but it was the only one the junkyard had- it was an F4, which have analogue gauges as well. Didn't expect it to work, but I was there and it was cheap. The Honda dealership has the part in stock, but, again, it is said to work for my bike too (which it shouldn't if this leads to my problem). So I guess I could get it and hope it's the one which gives the values that I need for my bike.

The only other option I can think of right now is to try to find a used one that I know came from an f4i. None of the housing on e-bay right now have one attached... which is kinda strange...

Edit: I am thinking that I can also temporarily wire in my temp gauge from the old cluster to see if it's getting the correct reading... Might be a pain in the butt...

 

Whoops, I'm going to go back a few steps here... The F4i doesn't appear to have the same thermosensor. Parts diagrams and Honda stores indicate that it does, but the manual says otherwise.... It's sensor is built into the unit that sends the signal to the ECM. This is going to take some further looking into.

Ok, now we're getting somewhere.

 

Maybe part #21 here : Honda, ATV Parts, Scooter Parts, Motorcycle Parts,CRF,CR,MX Parts, Goldwing parts

 

Hawkster8541- I just picked one of those up at the junkyard to see if I can retrofit it. The thermosensor doesn't actually exist on the F4I (but there is still a casting area in the housing, which I think may have caused confusion in the parts diagrams). In the wiring diagram, the unit that you pointed out sends a signal to the gauges, so I'm going to see if I can re-wire the harness/plugs to fig the new unit. More to come tomorrow...

 

Ok, it's too early to tell for sure, but I believe that I got everything working.

Here's what was happening. In the VTR, the thermosensor that sends a signal to the ECM is a different piece from the one that sends a signal to the gauges. Three wires total came out of the unit; two plugged into the green piece in my pic, and one into the gauge thermosensor.


In more modern bikes, these three wires are all arranged into one plug (the one on the right), and there isn't a smaller thermosensor for the gauges. Well, the threads on the three pronged piece seemed to fit in my thermostat... The ECM signal seemed to be the same... so I wired it in. And when I started my bike after about 10 seconds of a blank screen, it read at 107 degrees F. So... it worked?


The bike runs, I still have to get an infared thermometer to be sure, but damned if that worked!

Took a whole day to get a couple little numbers on the gauges! haha

Just tuned it to pass emissions as it failed that on Friday. Whoops, guess good ole Maricopa county, AZ thinks my bike is the city's pollution problem, not all of these extended cab F-250's driving around with one person in them and all that towing capacity to haul a larger sub woofer and 35" tires.

 

Well... Are we back to assumptions, or did you actually measure it?

The VTR termosensor goes from low to high resistance with increasing temperature, the ECT goes from high to low...

The F4i termosensor goes from high to low, ie the inverse from the VTR... Hence your earlier trouble...

The ECT however is never specified in the manual how to test or troubleshoot... Ie the only way to tell if it's giving off the correct signal to the ECU is to measure it out and compare to the VTR ECT...

Because if you just assumed, the ECU is now possibly running on completely screwed up temp readings for the ignition... And that's not going to make for nice tuning...

I'm genuinely interested... Since the temp sensor I'm using for the CBR gauges is "almost" correct on the temp, but not quite, i would like to swap in the CBR sensor if the ECT part is the same... Then both gauges and ECU get's the absolute correct signals...

 

Tweety, I was TOTALLY making assumptions on the signals sent to the ECM. I couldn't make heads or tails either, because like you said there is no trouble shooting procedure in either manual. The bike ran, so I just tucked that little question away... and you had to go bring it up!

So I think that what I need to look at doing is to measure the signal sent from the thermosensor to the ECM with the new unit that I have, and then put the old one back in (in similar temperature and running conditions) and see if the signals are the same...

Again, I am sort of making assumptions, but based on the resistance needs for the old gauges compared to the new ones and the needs of the ECM, having the new unit be one piece (that reads from high to low with increasing temperature) would make sense...

Edit: I don't even think that I need the part in the bike to do this, correct? I could just put both units in water and measure their resistance at a range of temperatures and compare.

For some reason, I was thinking that because the bike turned on before, it was working... ECM adjusting ignition timing based on temp didn't even cross my mind. Although, it never actually occurred to me to even consider why the plug was there in the first place . Still so much to learn...

 

Sorry, I'll stop thinking now...

My suggestion would be a pan of water or cooling fluid on the stove, and a thermometer... You have the specs for the VTR ECT in the VTR manual, just compare the F4i at the specified temps... If they give resonably the same values within 10%, you are good to go...

 

Yep, water on stove + multimeter is how yruyur and I tested the pre/post 01 sensors.

 

That one takes some dexterity! Even with two people it was really hard to get an accurate reading, but good news is that I think the ECT sensor is in the working range of my ECM.

Spec says between 2-3k ohms at 20 degrees C. I'm at 1.9k ohms and around 23 degrees, so it's close, an in the right direction.

At a 80 degrees C it's supposed to read between 200-400 ohms.
I read it at 82 degrees C and it was at 195 ohms.

Because as temp increases, resistance decreases, these readings appear to be within spec, or very close. So I guess I got awesomely lucky, and I'm going to go plug this thing back in.

BTW I took the pic before I realized that the sensor was touching the bottom of the pan, and fixed it before I took my readings

 

Then, I'd say score one for lucky guesses...

Yeah, those numbers are well within what I'd consider at spec... So, that means you can replace both sensors with a ECT from the newer CBR's... Just a Q... where did you get the plug? junkyard? I guess it's not going to be chap/easy to find...

 

It's about time I had some luck with this thing ... although I guess I'd consider low compression being just a valve issue and not a piston ring or something pretty good too!

Junkyard. I actually just asked for the thermostat and it was plugged into that (I took it off for $15). It looks like you can find thermostats on e-bay for the newer cbr's. The tricky part was the plug to the wiring harness. I just weeded through a pile of harnesses till I found one that sort of fit. By sort of, I mean the prongs were laid out in a triangle correctly, but I had to grind off a snap feature to make it fit and while the wires are waterproof, the connection is not. Hot glue, haha!?

There were a bunch of these plugs at the junkyard if you want me to pick you one up next time I'm there (I can look for an ECT sensor if you'd like too).

 

The sensor isn't an issue... I have at least one of those lying around from when I was considering it an option to stick one in a lathe and make it fit instead of the thermosensor on the VTR... The plugs though, seems a no-go around here... Last i suggested I wanted to by a plug at the local wrecker I got the reply that one plug or the whole harness didn't matter, the price was the same (it was even expensive for the harness...)

So if you are willing to stick one of those in an envelope, I'll gladly pay you what you pay for it, and shipping... I'll PM you tomorrow, gotta get some sleep now...

 

Ok, I have to run by and see if I can find a fan switch before I order one online so I'll grab one then...

 

Got the front turn signals in (and added a few bugs to the screen!)


They're just little guys, but more than nothing I suppose.

So, just going to re-cover the seat and everything on my "to do" list will be done as far as the initial round of mods.

Now I just gotta figure out why it cuts out at high RPM's and to get the carbs to stop sneezing at idle. Seems there are a lot of threads on these for me to weed through

 

With the exception of replacing a couple of broken carb pieces... yeah I finally snapped the little choke guide thingies, and whaddya know I'm running rich ,

The bike is finally "done"

Not quite sure where to start, but the before and after photos aren't even recognizable as the same bike (although a lot of it is!) I started the project knowing only how to change my fluids and adjust the chain, and now I can tell what half the pieces are with my eyes closed... and can get my way around it better than my mechanic...

The knowledge and help from the forum built this bike- I would not have had any idea where to start or how to work on this thing correctly without all the gearheads on here. Thanks guys...seriously, I'll never look at a motorcycle the same again! Plus, this thing keeps me

 

very nice!