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Daily Bird has a strange issue.

Sometimes when I pull into my garage and switch off the analogue gauge instantly pings up so the needle is sitting against the stop pin (almost 12 o clock)
The needle stays there until I have allowed the motor to cool. Then switch on the ignition and the needle drops to it's cold position (or nearly cold if I don't wait too long). If I leave the bike for days without switching on the ignition the needle will stay against the stop.

This problem only seems to happen if the fan has been running (or is about to) as I pull into my garage i.e. the motor is at the hot end of the scale.

This has been happening for some time (couple of years since I first noticed it!) and my initial thought was that it was due to the corroded (and bridged) PCB on the back of the clocks. I eventually managed to find a good PCB but the issue stays with the bike. I've checked and cleaned the temp sensor switch/connections and checked the fan connections and found nothing wrong. Loom earth bundle all fine.

Any ideas?

As a side note recent rides have highlighted another cooling issue that may/may not be related. We all know the Bird will run hot if there isn't air passing through the radiator. What I have noticed is that my temp gauge climbs much faster than it ever has. This is to the extent that it moves from just above cold to max (fan on) in less than 2 minutes if I have been riding and have to stop at traffic lights. Rad clear, coolant just changed (no air lock), thermostat is now 6 years old (seems only yesterday when I changed it) the original was 14 years old and still functioning fine, this one has seen much less life than the preivous one which covered 50k more miles! Rad cap is a Honda car one changed less than 2 years ago.

Again any ideas?
 

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First question has to be is the water getting to fan on temp when the fan switches on or is it coming on early?
Have you the early system where fan is switched by sensor on rad or by common sensor on block via ecu?
 

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Discussion Starter #3
I can only assume that the water is fully up to temp because you instantly feel the hot blast on the leg.
Sensor on the rad (manual switch also)
 

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Circulation issue?, although water must be going round to warm up the sensor on rad, could it be pump not flowing fully hence water not being cooled as quickly as normal?
Reckon that the gauge is probably not related- that one would tend towards fault in the gauge stopping the needle returning till power on
 

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Yes I thought of the pump originally, even pulled it and no wear that could be seen / measured. A thermostat check/change should rule out circulation issues.

The gauge probably isn't related and I'm almost certain the problem is 'electrical'. The gauge should be free to drop back down and it does just as long as the needle has not gone past 10 o'clock when the ignition is turned off. If it has then the moment you turn the ignition off the needle hits the stop only to drop back down when the engine (coolant) has cooled and ignition is turned on. The difference that I can see is that if the fan is on (or just about to be on) when the ignition is turned off then the gauge misbehaves but if the motor is cooler then the gauge behaves normally.
 

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Reminds me of the time when Roy was driving a bunch of us around on a sunday morning looking for an open bar (irrelavent story buildup) when he noticed the
temp gauge was "pegged". "The gauge is broken" was his claim. 10 mins later the car boiled over. "First the gauge, then she boils over, what's next?"

In other words, I wouldn't assume its not related.

Anyway, from all the way over here it sounds like the cooling system is working, but you are getting bad info from the gauge. Gauge/ temp sending unit?
 

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At the risk of insulting you by stating the obvious, did you check the drive dog was ok and it's corresponding socket was driven by the engine?
No insult taken it is just that sort of thing that can me missed but no, checked.
 

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Discussion Starter #9
Anyway, from all the way over here it sounds like the cooling system is working, but you are getting bad info from the gauge. Gauge/ temp sending unit?
I've even swapped the gauge over when I changed the PCB..... but I can't remember which one is in there now! (Doh). Temp sensor has only seen 3 summers.

Anyway, I'm planning another tour for later this year. Down through France around Northern Spain and then down/across to Northern Portugal ..... then back. I'm thinking I need to spend some time refreshing and proving the cooling system well before I leave, it should be hot over there!
 

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HI This is why im changing my coolant and thermostat when im on the move temp gauge right down
but at the first set of lights temp gauge goes up quickly until i get going again then drops
 

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So you've changed the thermocouple sensor? That could be failing. If internal short it would read 0 if open then it fails high or could it be picking up voltage from somewhere when the fan starts?

Sent from my SM-N960U using Tapatalk
 

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Yes I've changed it XXGUY but just because the original lasted for years doesn't mean the new one will! You have picked up on one of the many thoughts that are passing through my brain, I really need to drag myself away from the DR and get this sorted ......
 

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Duck
Thinking XX may have something there. What may be happening is your getting feedback spike. I'll bet it's hitting the gauge and sticking the needle at 12. When you cycle the key after it's cooled some the normal voltage pulls the needle back to home. Problem is going to be trying to catch the spike if that's what it is. You could pull the gauge face and see if the needle is jamming. When it 12's try touching the end of the needle and see if it drops back. If it does then all you have to do is find the source of the feed back. If not then you should be able to read the voltage with a dvm and then start taking things off line. I'd start at the fuse box and pull fuses to see if anything is bleeding over. It could well be a bad grounding causing feed back.

We had a project goldwing in class that had a broken ground lead in the right rear tail running light. It caused the dash, turn and running lights to come on dimly. The running lights you might suspect but the dash and turn signals were the weird part of the feedback.
 

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Discussion Starter #14
Thanks beestoys seems like we are all thinking on the same lines that's why I initially suspected the corroded PBC as being the cause especially the earth tracks. When I had the clocks out I checked the gauge needle and it is not free to return when stuck at 12.00. I also checked continuity from the clocks to the earth bundle.

As a side note a couple of days ago I went to start the bike and the battery was flat. Charged up and rode but on my return I checked for leakage. 0.5mA on the main earth cable, 0.5mA main earth cable + earth cable for additional fuze box but 15.2mA main earth cable + separate earth cable for USB charger! El Cheepo charger (only ever used on long foreign trips) quickly removed!

My wife going away next weekend so there will be space in the garage without her bike, time to pull Daily Bird apart!
 

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Ummmm, you guys are prob more into this than me, but, what was that comment about the radatior cap being from a Honda car? I assume it is the correct pressure rating.... but i suggest it as when I was installing a new rad in my old car, I reused the old nissan cap as I figured it was still young and I had problems until I put a brand new rad cap on again.

Hope it is just that simple..... BB can run to 109C here in Aus, but the Honda 50/50 coolant is good to 123C from memory....... last time I rode mine it was a steady climb to 109C at lights not a fast run up the dial. Normal cruise in fresh air is around 84C.
 

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Ummmm, you guys are prob more into this than me, but, what was that comment about the radatior cap being from a Honda car? I assume it is the correct pressure rating.... .
Yes correct pressure rating. The reason we take this route is that a Honda item for the Bird costs £40.66 in the UK, I picked up two Honda car items for £11 from my local motor factors.
 

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Yes correct pressure rating. The reason we take this route is that a Honda item for the Bird costs £40.66 in the UK, I picked up two Honda car items for £11 from my local motor factors.
Any chance you have a part number for those car caps please ?
 

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Well I dragged myself away from the DR today and sorted (?) Daily Bird.

Thermostat replaced, yes it is easy to do just by lifting the rear of the tank, no need to take the tank off, a relief to me since I had stupidly brimmed the tank two days ago. The old one tested fine.

Rad cap replaced because I have a spare new item.

Water pump replaced ... because I had a low mileage spare.

Temp sensor replaced on rad. Now that is where things get 'interesting' (non nerds need to look away now). This aftermarket one was sold for the Bird but came marked as opening at 85 dec C, (i.e. turns the fan on at 85 dec C) so I decided to test the one that I had taken out in my powder coating oven. The removed one was was also sold as a Bird item but had no markings. Test showed the old one turned the fan on at 100 deg C (or very close to).

Having found that out I realised that I didn't know what the OE switch should turn the fan on at! Anybody know? Past experience says close to 100C but I don't know if the OE item comes with a marking.

The result of my work is that the fan now comes on 'early' so I can't replicate my original fault where the gauge needle hits 12 O'Clock but with the fan running earlier I can imagine I am putting more stress on the charging system ....... but this set up should be a real bonus in the hotter climes of my 'tours' .... oh yes, plans have changed due to lack of ferries when I wanted to travel this year (and my wife's lack of enthusiasm for ferries) so instead of Spain/Portugal looks like I'm heading back to the Balkans this year :thumb: Didn't spend enough time there so I really fancy a return visit :smilebig:
 

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the thermostat was far easier than i thought i found if you remove the hoses first gives much more room ,and a long extension
for the bottom bolt worked well
 
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