Thanks for the Information
Article [13] ST1300 - Spoiler fitting
- Thread starter Spotthegerbil
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- Mar 18, 2006
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- 2013 ST1300 A9
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- 003355
This isn't a new idea and has been mentioned before in these forums. But when I needed it, I couldn't find what I was looking for in one place.
A (very expensive) addition to the Honda top box is the colour matched spoiler. It comes complete with a row of high intensity Red LEDs which are plumbed into the brake light circuit. High level brake lights are now a legal requirement for all new cars in the UK. They are a pretty good idea on the ST1300 too.
However, if you have ever followed another ST1300 in poor daylight, you soon realise how poor the rear lights are. This little modification converts the LED brake lights into a tail/stop light. It requires a few electronic components - 2 diodes (or rectifiers) and a resisitor, some wire and (optional) a couple of electrical connectors.
The idea is to feed the LEDs with two power inputs. One from the brake light circuit, another from the tail light circuit, but at a reduced voltage. The diodes are there to prevent the power from the brake light circuit flowing into the tail light circuit and vice versa.
Nb - this modification does reduce the intensity of the brake light slightly, but really, if I hadn't told you, you wouldn't have known. It is still very effective .
It took a little experimenting to get a resistor of the right value. The tail light mustn't be too bright, or it won't be possible to tell when the brake light comes on. Too dim, and there is no point in having it !
A split image showing - left side showing the tail light, right side showing the brake light.
Circuit diagram The 3 wires from the left are tapped into the 3 leads going to the tail stop light.
Green = Earth
Brown = Tail Light
Yellow / Green = Brake light
Please check the colours of the leads to your tail light rather than relying on the ones shown here.
The two wires on the right go to the LED brake light.
The two diodes are 1N5400 - more than big enough for the job
The resistor is 220 ohm, 7 watts. Again, I've gone for overkill.
The photo above shows the components laid out on the circuit diagram.
The second photo of the diode shows the orientation - that grey stripe at the end is in the same location as indicated by the black bar on the diagram - in this case pointing to the right.
Note the white connector on the right is designed to fit into the connector provided with the Honda spoiler. Check that the colours of the wires match before connecting together.
The green connector on the left is optional. There is nothing to plug it into unless you put the female part in place yourself. The alternative is to hard wire it in place. I prefer to have connectors - it makes it easier to replace the module if necessary. In fact, in the event of failure, I have a simple lead which connects the green connector to the white to reinstate the LED as a standard brake light.
A shot showing how I wired this up. The size of the resistor in its hard rectangular ceramic case makes a sturdy device to which the diodes can be secured to prevent the soldered joint from ' work hardening' from vibration.
The diodes were taped to the resistor and the ensemble was then put into a length of 3.5cm wide heat shrink tubing and effectively shrink-wrapped .
The photo shows TWO wires at the left hand end and ONE wire on the right. The flash has created a shadow which looks like an additional wire. The photo does not show the green earth wire which simply passes from one side to the other.
On the left
My orange lead connects to the brown tail light lead.
My yellow lead connects to the green/yellow brake light lead
On the right, the yellow lead connects to the spoiler yellow/green lead.
To get at the wiring for the tail stop light, remove the rear mudflap - 4 bolts. The rear light holders can be removed (best to undo both sides. The right lamp holder is connected to the wiring loom, the left is connected to the right. I found that there was more wiring to play with on the right hand bulb holder. Best to remove the bulbs (don't touch with fingers), otherwise you risk breaking them and kneeling on the broken glass. If you decide to cut and crimp on new connectors, make sure you have enough length of wire to operate the crimp pliers. You might need to work closer to the bulb holder than you would prefer.
Alternatively, you could break into the main harness under the pillion seat on the right hand side to splice into the wires.
NB - Make absolutely certain that you have the diodes facing in the correct direction - that grey band must face in the direction of the LED wire. Also make certain that the connector wires are in their correct place.
In the UK, Hitachi connectors can be found at SG Motorsports.
In USA this is one supplier mentioned in a different post http://www.electricalconnection.com/
Diodes and resistors bought over the internet from Maplins (UK)
Note that on the hitachi connectors used by Honda, one side has a locating groove. The earth wire is always fitted next to the side with the groove.
A (very expensive) addition to the Honda top box is the colour matched spoiler. It comes complete with a row of high intensity Red LEDs which are plumbed into the brake light circuit. High level brake lights are now a legal requirement for all new cars in the UK. They are a pretty good idea on the ST1300 too.
However, if you have ever followed another ST1300 in poor daylight, you soon realise how poor the rear lights are. This little modification converts the LED brake lights into a tail/stop light. It requires a few electronic components - 2 diodes (or rectifiers) and a resisitor, some wire and (optional) a couple of electrical connectors.
The idea is to feed the LEDs with two power inputs. One from the brake light circuit, another from the tail light circuit, but at a reduced voltage. The diodes are there to prevent the power from the brake light circuit flowing into the tail light circuit and vice versa.
Nb - this modification does reduce the intensity of the brake light slightly, but really, if I hadn't told you, you wouldn't have known. It is still very effective .
It took a little experimenting to get a resistor of the right value. The tail light mustn't be too bright, or it won't be possible to tell when the brake light comes on. Too dim, and there is no point in having it !
A split image showing - left side showing the tail light, right side showing the brake light.
Circuit diagram The 3 wires from the left are tapped into the 3 leads going to the tail stop light.
Green = Earth
Brown = Tail Light
Yellow / Green = Brake light
Please check the colours of the leads to your tail light rather than relying on the ones shown here.
The two wires on the right go to the LED brake light.
The two diodes are 1N5400 - more than big enough for the job
The resistor is 220 ohm, 7 watts. Again, I've gone for overkill.
The photo above shows the components laid out on the circuit diagram.
The second photo of the diode shows the orientation - that grey stripe at the end is in the same location as indicated by the black bar on the diagram - in this case pointing to the right.
Note the white connector on the right is designed to fit into the connector provided with the Honda spoiler. Check that the colours of the wires match before connecting together.
The green connector on the left is optional. There is nothing to plug it into unless you put the female part in place yourself. The alternative is to hard wire it in place. I prefer to have connectors - it makes it easier to replace the module if necessary. In fact, in the event of failure, I have a simple lead which connects the green connector to the white to reinstate the LED as a standard brake light.
A shot showing how I wired this up. The size of the resistor in its hard rectangular ceramic case makes a sturdy device to which the diodes can be secured to prevent the soldered joint from ' work hardening' from vibration.
The diodes were taped to the resistor and the ensemble was then put into a length of 3.5cm wide heat shrink tubing and effectively shrink-wrapped .
The photo shows TWO wires at the left hand end and ONE wire on the right. The flash has created a shadow which looks like an additional wire. The photo does not show the green earth wire which simply passes from one side to the other.
On the left
My orange lead connects to the brown tail light lead.
My yellow lead connects to the green/yellow brake light lead
On the right, the yellow lead connects to the spoiler yellow/green lead.
To get at the wiring for the tail stop light, remove the rear mudflap - 4 bolts. The rear light holders can be removed (best to undo both sides. The right lamp holder is connected to the wiring loom, the left is connected to the right. I found that there was more wiring to play with on the right hand bulb holder. Best to remove the bulbs (don't touch with fingers), otherwise you risk breaking them and kneeling on the broken glass. If you decide to cut and crimp on new connectors, make sure you have enough length of wire to operate the crimp pliers. You might need to work closer to the bulb holder than you would prefer.
Alternatively, you could break into the main harness under the pillion seat on the right hand side to splice into the wires.
NB - Make absolutely certain that you have the diodes facing in the correct direction - that grey band must face in the direction of the LED wire. Also make certain that the connector wires are in their correct place.
In the UK, Hitachi connectors can be found at SG Motorsports.
In USA this is one supplier mentioned in a different post http://www.electricalconnection.com/
Diodes and resistors bought over the internet from Maplins (UK)
Note that on the hitachi connectors used by Honda, one side has a locating groove. The earth wire is always fitted next to the side with the groove.
Last edited:
- Joined
- Mar 18, 2006
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- 430
- Location
- Ilkley, W Yorkshire, UK
- Bike
- 2013 ST1300 A9
- 2025 Miles
- 003355
I doubt that it really matters - but I never found out how much current the LED lights actually used. Probably much less than couple of 5w tail lamps - but since I didn't know I went for 7w. Again, unnecessarily erring on the safe side, I'd fit the 10w if I was doing this again and 5w and 10w were my only options, even though my suspicion is that it would use much less power than that.
So 5w is probably ok. 10w is definitely ok (because mine has been OK for years with a 7w resisitor ! The figure for the wattage of a resistor is an indication of the maximum power that the resistor can have passing through it. It needs to be a high enough to cope with the power - otherwise bits of it melt ! It's not like a headlight bulb where the wattage represents the amount of power that the bulb consumes.
220 ohms was the best compromise for me for getting a bright enough tail light, but dim enough for the brake light to be significantly brighter.
But that way (10w) you know that it can handle whatever power the tail light requires without the risk of overheating. The larger ceramic block gives a much more solid structure to support the wiring and diodes. Its important that those joints cannot move relative to each other. I used heat shrink tubing, but strapping it with tape to the body of the resistor will do the same job.
So 5w is probably ok. 10w is definitely ok (because mine has been OK for years with a 7w resisitor ! The figure for the wattage of a resistor is an indication of the maximum power that the resistor can have passing through it. It needs to be a high enough to cope with the power - otherwise bits of it melt ! It's not like a headlight bulb where the wattage represents the amount of power that the bulb consumes.
220 ohms was the best compromise for me for getting a bright enough tail light, but dim enough for the brake light to be significantly brighter.
But that way (10w) you know that it can handle whatever power the tail light requires without the risk of overheating. The larger ceramic block gives a much more solid structure to support the wiring and diodes. Its important that those joints cannot move relative to each other. I used heat shrink tubing, but strapping it with tape to the body of the resistor will do the same job.
Last edited:
ST Gui
240Robert
+1 The thing about most motorcycles is the brake lights and tail lights share the same lens/lenes so the difference is the level of brightness. Those lenses are often lower than the following driver's line of sight or concentration.
After the development of the CyberLight and SF's trial of center high-mounted stop lights on taxis DOT required the CHMSL on passenger vehicles. That light was a dedicated brake light not a tail light aka running light. The mounting position and brake light only function as been shown to reduce rear-end collisions. Not guarantee they won't happen but a move to reduce them.
I've always wanted a Honda top box and only because of that slick spoiler LED. Going from dark to brakelight-bright has an edge IMNSHO over a tail light brake light combo. So if you chose to combine the functions on the LED you'll want to ensure there's adequate difference in brightness so that it not only acts as a brakelight but looks like one too.
Once you get it wired up as a combo you could add an LED flasher that flashes the brakelight momentarily then keeps it on steadily.
[edit] Ok I somehow completely missed John's that cover all the salient points and then some.
Last edited:
- Joined
- Mar 18, 2006
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- 430
- Location
- Ilkley, W Yorkshire, UK
- Bike
- 2013 ST1300 A9
- 2025 Miles
- 003355
That is an interesting and important perspective @ST Gui .
When I bought the spoiler, I wanted it primarily as a better rear light. I reckoned that the normal stop lights were bright enough, but having ridden behind many other ST1300s the tail light might as well not be on in some low light daytime conditions. Like car sidelights in fog. You see the car before you see the lights.
But those LEDs are very bright and would dazzle and distract if they were used unresisted as an extra tail light rather than a brake light.
I experimented with combinations of 100, 220, 370 resistors - I bought 2 of each and wired in various series / parallel combinations and checked in daylight from the end of the drive with the bike in the dark garage, and with the bike out in the daylight. Long bit of string on the front brake lever. Just visual assessment using the Goldilocks sample and eliminate process. Too bright, too dim, just right.
Then the ultimate scientific test of someone riding behind me and passing comment. "Yes, that'll do."
The Diode does drop the raw brightness of the stop light, you notice it if you have seen it operate as intended as just a brake light. But but it is plenty good enough even with the diodes 0.7v drop.
I did consider a relay circuit to get the full voltage through, but when I saw how effective it was with the diode / resistor solution, it simply wasn't worth the hassle.
My first attempt was with lower quality resistors that looked similar to the diodes. The resistors didn't fail or burn out, but it was impossible to join them together in a way that was robust. The wires broke off where they met the diode or resistor casing. That large ceramic rectangular block keeps everything nicely strapped together and has been on this bike for over 50,000 miles. I did make a spare but have never needed it.
When I bought the spoiler, I wanted it primarily as a better rear light. I reckoned that the normal stop lights were bright enough, but having ridden behind many other ST1300s the tail light might as well not be on in some low light daytime conditions. Like car sidelights in fog. You see the car before you see the lights.
But those LEDs are very bright and would dazzle and distract if they were used unresisted as an extra tail light rather than a brake light.
I experimented with combinations of 100, 220, 370 resistors - I bought 2 of each and wired in various series / parallel combinations and checked in daylight from the end of the drive with the bike in the dark garage, and with the bike out in the daylight. Long bit of string on the front brake lever. Just visual assessment using the Goldilocks sample and eliminate process. Too bright, too dim, just right.
Then the ultimate scientific test of someone riding behind me and passing comment. "Yes, that'll do."
The Diode does drop the raw brightness of the stop light, you notice it if you have seen it operate as intended as just a brake light. But but it is plenty good enough even with the diodes 0.7v drop.
I did consider a relay circuit to get the full voltage through, but when I saw how effective it was with the diode / resistor solution, it simply wasn't worth the hassle.
My first attempt was with lower quality resistors that looked similar to the diodes. The resistors didn't fail or burn out, but it was impossible to join them together in a way that was robust. The wires broke off where they met the diode or resistor casing. That large ceramic rectangular block keeps everything nicely strapped together and has been on this bike for over 50,000 miles. I did make a spare but have never needed it.
Last edited:
Andrew Shadow
Site Supporter
Installing the below top case allowed me to solve both the issue of being more noticeable and having an extra dedictaed brake light, as well as giving me me a place to store my helmet.
There are three sets of LED's in this top case.
The lower level light assembly is actually a row of LED clusters. Each bright spot is actually a cluster of five small LED's. They are wired so that two LED's of each cluster illuminate when one wire is powered. The remaining three LED's of each cluster illuminate when a second wire is powered. You can connect them to 12V + in any way that you wish.
I wired them so that two LED's of each cluster are powered all the time as running lights. The other three LED's in each cluster are connected to the brake light circuit.
The top light is a dedicated LED brake light that comes on at full brightness only when the brakes are applied.
I installed a flasher unit that flashes the brake lights quickly initially, then the flashing slows to where the brake lights stay on.
This gives me a row of double LED clusters burning constantly as running lights up high on the bike. When I apply the brakes, the second row of three LED clusters and the upper dedicated brake light come on in a rapidly flashing pattern that slows to brake lights constantly burning. All of them up high and the full width of the bike. It seems to work very well. The row of running lights are not particularly noticeable during bright daylight, but I have been told that in lower light conditions and at night it is impossible not to see. I also have the Garry Rowe LED brake light mounted on the rear grab rail platform, also connected to the flasher. I have been told that the brake lights are very attention getting.
- Joined
- Mar 18, 2006
- Messages
- 430
- Location
- Ilkley, W Yorkshire, UK
- Bike
- 2013 ST1300 A9
- 2025 Miles
- 003355
Nice solution - and it gets around the weight limit issue. That Honda spoiler is very heavy and it then becomes part of the permitted load of the top box. Honda don't reveal what additional downforce is added by having the airflow spoiler on the back !!
I just got a white st1300 with every addon possible including the topbox spoiler which is not wired up or if it is i cant find the connecting lead.
My topbox also has the armrests and overall i find the lid very heavy now.
Im not a fan of cutting into looms. On a post somewhere it mentions a brake light connecter in the rubber boot front right side near the top.
I have full led bulbs in the rear tail lights orange ones in the indicators red in the brake light and i have no issue being seen.
So sadly im not keeping the spoiler but because its all bolted on i will have to find someone to swap with for another white topbox
or look to buy one and then just sell mine.
I dont really get the point of the spoiler its both heavy and expensive
My topbox also has the armrests and overall i find the lid very heavy now.
Im not a fan of cutting into looms. On a post somewhere it mentions a brake light connecter in the rubber boot front right side near the top.
I have full led bulbs in the rear tail lights orange ones in the indicators red in the brake light and i have no issue being seen.
So sadly im not keeping the spoiler but because its all bolted on i will have to find someone to swap with for another white topbox
or look to buy one and then just sell mine.
I dont really get the point of the spoiler its both heavy and expensive
ST Gui
240Robert
I don't remember if it has a tail light and brake light or just a brake light. I like the idea of a dedicated CHMSL/third brake light. It's high up and closer to the line of sight to drivers behind you.
Obviously there's no guarantee but third brake lights have reduced rear end collisions in general. So if I had a top box with one it would be wired only as a brake light. I might even put one of the superbrightled.com momentary flashers inline with the brake light. It flashes four times fast then four time slow then full stop. (lol)
I also like the spoiler's look just like I do the spoilers of many cars. Sure it's almost 100% an aesthetic affectation but I don't care.
If none of that is of your preference then selling that top box with spoiler should get you a fair price.
Last edited:
- Joined
- Mar 18, 2006
- Messages
- 430
- Location
- Ilkley, W Yorkshire, UK
- Bike
- 2013 ST1300 A9
- 2025 Miles
- 003355
The spoiler is just an extra brake light. My mod to make it into a tail light / stop light is here. Post 42
www.st-owners.com
Article [13] - ST1300 - Spoiler fitting | ST1300 Articles
Thanks for the Information
ST Gui
240Robert
Ah. Thanks for the info. My extra brake light is fitted into the STock black plastic pad that's part of the ST's rack. It's not in drivers' line of sight like the spoiler's light if they stop a little close. I've got the flasher mentioned in my earlier post but I haven't got 'round to installing it.
At one point I really wanted the factory topbox. But I've passed on the idea as well as any topbox. But if I did get a factory box with spoiler I'd add a discrete tail light and not add it to the brake light. I'd do similar with a non-factory box – discrete brake and tail lights.
Andrew Shadow
Site Supporter
One of the few who got that little bit of Gary Rowe ingenuity. It is a smart little product, I have one as well.
I also have a top box that has wrap-around LED lights that can be tail or brake lights or both. It also has another seperate higher mounted set of LED lights that is used as a brake light only. This combination makes me more visible and gives me two additional brake lights, one mounted up very high. Both supplemental brake lights are wired through the SupetBright flasher unit that you mentioned.