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Home Repair And Restoration

CBF 125 Side Stand Switch Problem

The bit you're interested in.

Do you have or suspect you have a CBF 125 side stand switch problem?  The wires from the side stand switch run from the switch behind the front sprocket cover and into a connector under a rubber boot behind the left hand side panel behind the fuel pump.  This can be accessed by simply removing the left hand side panel.  Look for 2 wires, one green, one green and white (09 model).  The sidestand switch should be CLOSED when up and in the riding position.  That means the green and green/white wires are connected.  If you suspect a dodgy switch short these wires out preferably at the connector.  

small plastic cbf 125 side stand switch connector block
The shorted out connector block on the side stand switch side.  Now soldered and taped up.  Temporary repair only...

The story.

It never rains, it just pours.  You ride a bike for 6,000 miles with no issues whatsoever just regular maintenance and some brake pads.  The if you're a regular reader you'll know there were some issues with the fuel pump last Tuesday.  This Wednesday morning the bike started fine but would not run as soon as I dropped it into gear.  Side stand switch.  A couple of up and down sweeps of the sidestand and we were off.  Just a bit of muck I reckoned on the contacts.

All was fine.  In fact since I had my mysterious fuel pump issue that mysteriously disappeared the bike has been running better than ever!  She feels sharper, crisper and better fueled.  I suspect there was something in the fuel pump that ought not to have been.  I enjoyed a perfectly fine if slightly chilly 25 mile ride to work with no alarms and no surprises.  My riding wasn't the best but who's is at 0600.

I say I rode 25 miles, more like 24.5 because on the last roundabout the bike cut out again.  Nothing, nicht, nada.  After freewheeling just enough to avoid being rear-ended by the typically impatient car driver I pulled onto the actual roundabout island that is fortuitously paved.  I moved the sidestand up and down a few times to no avail.  The CBF started perfectly but as soon as a gear was engaged the motor was cut.

I took a moment to think.  That is exactly what I'd expect to happen if I'd left the side stand down.  Could it be any other switch or safety system?  Clutch switch?  No, if the computer thinks the side stand IS up then the clutch switch is ignored otherwise you can't ride the bike.  Neutral switch?  No, same reason as the clutch and the neutral light is working fine.  No, I'm fairly sure it's the side stand switch.

The tool kit on my CBF is either very poor or there's some bits missing.  Luckily there's a screwdriver which allowed me to get the side panel off.  I found what I THOUGHT...HOPED were the wires for the side stand, and a connector hidden behind the fuel pump (coincidence?).  Having unplugged the connector I doubted that would solve the problem, previous Honda 125 experience tells me the sidestand switches are usually CLOSED when up and in the riding position.

I'm was correct, same issue.  I needed to short the wires out to trick the computer into thinking the stand is up.  Of course there's no pliers, wire cutters, wire strippers or soldering kit in the tool pouch, just the screwdriver and a couple of spanners.  Using the screwdriver I scraped and scraped and scraped and scraped at the insulation.  I of course dug the screwdriver into my fingers several times coating the wires and copper in blood.  

After much digging I finally exposed enough bare wire to twizzle the connector around and cause a short.  I plugged it back in and gave it a shot.  Bada Bing! We were running both in and out of gear.  I spent another age trying to put the pain-in-the-ass side panel back on.  I completed the last half mile and arrived at work, still 10 minutes before my official start time too.

It took a matter of minutes to remove the connector, solder it up and replace it.  It is a temporary fix but as long as it gets me about for a few days while I source a new side stand switch then I'll be happy.  Ho well, another job jobbed.  A cursory look on fleabay suggests the going price is around 15 to 20 pounds for a second hand one.  I wonder how much they are new?  I'm not so happy to leave it shorted out, setting off with the sidestand down is all too easy and quite dangerous.  I will however keep my little old shorted-out connector under the seat just in case it happens again.

Reader's Comments

Ren - The Ed said :-
Just found the part number for the side stand switch - 35070-KWF-950.

That'll be around £116 to you sir! Are they taking the michael or what?
01/01/2000 00:00:00 UTC
john said :-
Does it HAVE to be the same switch Ren? im sure a copy switch could be used without any problems from the cpu on the bike. that price is a piss take, or a misprint surly.
01/01/2000 00:00:00 UTC
Ren - The Ed said :-
Hi John

I've checked a few websites, nope that's the price at least from the sites I've seen. I have just ordered one from fleabay for £15. It is in fact an earth return, the green wire on Honda is usually the earth and checking the wiring diagram the green is earth and the green/white is a return to the ECU.

If I couldn't find a decent second hand one the plan was to rig a car door to courtesy light button up!. These are earth return and I'd have made a mount to fit the little button such that when the stand is up it closes.

Anyhow...later on I'll post something about the side stand switch I've just removed from the CBF...


01/01/2000 00:00:00 UTC
Rik T said :-
Glad I found this. Had some issue with the motor cutting out. Shorted the wires as you said and it's stopped. Looking like a new sidestand switch. Blooming expensive! What about leaving it shorted out?
01/01/2000 00:00:00 UTC
Ren - The Ed said :-
Rik! You really must get it fixed! It's all too easy to set off with the sidestand down. Then you come into a left hand corner, the sidestand digs in and spits you off...into oncoming traffic. Definitely a recipe for disaster.

If money is really tight I suggest removing the sidestand and just using the centrestand, you can't ride off with that down. Then when you've saved up or found a second hand switch you can replace the sidestand safely.
01/01/2000 00:00:00 UTC
Charles said :-
As long as the springs fine and tight on side stand you will be fine
19/05/2018 05:01:15 UTC
Ren - The Ed said :-
Hi Charles. Without a side stand switch there is always the risk of the side stand digging in on a left hander if it's been left down. That's why bikes have them fitted.

I always used to wonder what the piece of rubber on the side stand was for on earlier bikes without sidestand switches. Than I worked it out. That piece of rubber makes contact with the tarmac *JUST* before the metal stand does. This flicks the side stand up before the stand has chance to dig in.

So either you need a switch to stop you from riding off, a piece of rubber to flick the stand up if you can/do ride off or no side stand which solves the issue.

Side stand rubber CG125
19/05/2018 10:09:17 UTC

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