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Philip's Ravings

Fitting Oxford HotGrips

Rating: 5 votes, 4.80 average.
With another winter approaching and my woman complaining of my freezing cold hands after each ride (which I was sure to rush in when finished riding, rip my gloves off, and promptly place on her nice warm stomach) I decided it was time to look at the options available.

I have very limited mechanical abilities myself (to help you place your skills alongside mine if you’re going to do this yourself). But I have a lot of patience and perseverance and I try not to let the fear of making a mistake get in the way!

Heated grips seemed like the best solution. Oxford makes two products that suit, Heated Overgrips, and HotGrips. Overgrips fit over your existing grips. They are "easy" to put on (look a bit like a rolled up bandage), and take off if you sell your bike (or even if you just want to use them for the winter season only).
The look of the OverGrips didn't take my fancy. I also didn't like the idea of the OverGrips potentially slipping on the main grips.

HotGrips replace your existing grips, and you super-glue them in place. So they are permanent. If you put these on don't plan on ever taking them off your bike. There are a couple of styles, "original" and "sports". I have a sports bike so decided to get the sports variety. The original and sports differ only in their grip styling - nothing else.

When I got the HotGrips home I studied the instructions, and read lots of comments on line. The manual instructs you to wire the grips directly to the battery terminals. The HotGrips controller has a voltage detector and only runs while the voltage is above a preset level. I didn't like this idea, as if you stop the bike and forget to turn the HotGrips off they will continue to flatten the battery until it gets down to the preset voltage. Will this leave enough power in the battery to start the bike on a cold morning? To resolve this problem the manual suggests you buy an Oxford battery trickle charger.

Altogether it was not an approach I wanted to take. I decided I wanted the HotGrips to use an ignition switched source, so if the bike was off the power to the grips would also be cut off.

So I headed down to JayCar electronics, and bought a 15A automotive relay, and 3m of wire for minor cabling. I already had crimps and a crimping tool to terminate the wire that I would need to add.


So onto the main attraction. First job, remove the old grips. I had to remove the bar end weights first. Left hand side came off okay. Right hand side was a real bitch. The bolt just kept rotating and wouldn't undo. Spoke to someone about this and they said they had seen this before, and you have to use brute force and pull the whole mechanism out.
Well it took a lot of force, but I got it out. Discovered the internal bar weight was broken in two. Decided to take out the left hand internal bar weight, and low and behold, it was also broken in two as well. Compared the two broken pieces, and discovered that someone had replaced the bolt from the right hand bar end with the wrong bolt. It was oversize and too long. Probably contributed to it breaking.

Anyway, contacted Econohonda (on-line parts dealer in NZ for Honda parts) and they had everything I needed in stock, and sent up the replacement parts overnight.

Now back to the main job, removing the old grips. Tried several things, but what worked best was to squirt CRC between the grip and the bar. Seemed to dissolve the existing glue, and the existing grips slid off easily after that.

The manual said to remove any existing glue or residual as you want a tight fit. So I did this using sand paper. Tested the right hand grip and while it was firm it slid on nicely.
Onto the left hand grip. Even applying a lot of force I could not get the bastard on. Read the manual and it says the grip is designed for a bar with a 22mm diameter. It said if the grip is too tight check the inside of the grip for left over rubber from manufacturing (did that, couldn't see any) and make sure the bar is smooth (it was, just sanded it).
So now I had an issue with only two likely answers. Either the left bar was oversize, or the grip was under size.

So I went down to Repco and splashed out on some callipers so I could measure the two. The Oxford HotGrips had an internal diameter of exactly 22mm. So they were fine.
The bar had a diameter around 22.3mm. Bastard. The bar was painted black, and I bet the paint was causing the issue.
So I went back to sanding the left bar, and by the time I had sanded all the paint off the bar diameter had dropped down to just over 22mm. Tried the left HotGrip again. Very tight, but it did slide on, so decided to leave it at that. Would rather have it slightly tight that slightly loose.

You need to spend some time considering the actual placement of the right throttle grip, as that is also where your front brake lever is. You need a position for the grip so that when the throttle is rotated 100% open that the wire that comes out of the grip does not prevent the brake from operating at its maximum power (aka, you can still squeeze the brake lever all the way in). You also want to make sure you can operate the starter button ok. So spend some time thinking about this.
I ended up positioning the right hand grip so that when the throttle was closed the wire sticks almost straight towards the rear of the bike.

Now the cabling. When you run the cabling from the bars you need to choose a cable run that allows the throttle to fully open and close, and also still allow you to run the bars from full left lock to full right lock with no impediments. I screwed this up the first time. I ran some of the cables around the front of the left fork, and found the cables prevented the bars from obtaining full left lock easily (or would probably result in long term damage to the cables).
So I ended up re-laying the cables so they went around the outside of my forks, and then back down the side of the bike.

I removed the left fairing, and I cable tied all the excess cable and the controller module to the frame, in a little gap where there was another relay already (used for the horn).
I wired the "negative" lead to a ground point on the bike (same grounding point as used by the horn as it turns out).

Now the tough part. Where to break into a switched ignition cable. Headlight and tail light seemed good candidates as they both turn on and off when the key is turned on and off. I decided if something went "wrong" while I was riding I would rather lose my tail light than my head light.

I have the user manual for my bike, which includes an electrical schematic. Basically power goes from the battery into a 30A fuse, then into the ignition system, and then splits into 4 separate 10A circuits for "low power" circuits on the bike. I calculated the maximum loading of the lights fed from the stop light fuse, and it came to 3.9A. The HotGrips pull a maximum of 4A. So if I fed the HotGrips directly from this circuit it would peak out at 7.9A, or 79% of the fuses rated capacity.
I pulled out the fuse and stuck a multimeter across the fuse socket and measured the current being drawn. Only about 2A was being used with everything turned on (so several things obviously don't run at their full rated capacity).

So at this point I decided there was no point using a separate relay to switch the load. The ignition switched circuit I was planning on using had plenty of spare capacity.
So I ran a wire from the rear tail light at the back of the bike along the existing wiring loom to where I had located the controller. I crimped all the wires, which means I can unplug everything at a later date in case I need to service something.
I then used insulation tape and wrapped all connectors (both the crimped connectors I had added, and the HotGrip connectors) to make them more water resistant, and potentially stop any electrical "accident" from happening.

Now it was test time. Put the key in the bike, and turned the key to on. The Oxford controller came to life, and showed a blue flashing light. Checked the manual, and this means the battery is below the "preset" level, and it has turned off to save the battery. Seems well set for my bike.
Hit the starter button, headlight went off, and nothing. Hit the starter again, nothing. Fuck.
Then remember I had engaged the engine kill switch. I always do this when servicing the bike just in case an "accident" happens.
So with the switch in the run position, started the bike fine this time.

Blue light stayed on fine. Waited five minutes and the HotGrips got nice and warm.
Turned the bike back off.

Now I know everything was working it was time to super glue the grips on. I noted the angle of the cable of the left hand HotGrip relative to other things on the left bar. Pulled the left grip off. Ran super glue around the inside and outside of the bar, and then several lines up and down. Then shoved the grip back on, and quickly aligned it to the marks I had noted previously. You can't mess around at this stage. The super glue sets quickly. So make sure you are clear in your mind where you want the HotGrip positioned BEFORE sliding it on.

Repeated the process on the right hand Hot Grip. While the glue was setting I started cable tying everything up. Mostly I was just cable tying the new cables to the existing wiring loom.

Tested the throttle grip about 5 minutes later and it was resistant to moving. Fuck.
On closer examination what had happened was a bit of Super Glue had squeezed out between the grip and the end of the bar where the controls are. I have a fine thin file (a bit like an emery board or a nail file), so I slipped it in and gave it a file hoping to remove the excess glue. Fortunately this worked. Throttle can now rotate between fully open and fully close with no resistance or sticking.
So when you do it, be careful not to put too much glue near the inside of the right hand bar (the throttle bar) to avoid my issue.


And that concluded my experience. I hope the little traps and experience I have shared will help prevent you running into some of the problems that I did.

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Comments

  1. CookMySock's Avatar
    Great writeup!
  2. been_there's Avatar
    Nice one...Will come in useful when doing mine
  3. davebullet's Avatar
    Good stuff.

    Do several dry fittings. As in if you can't slide the grips on in < 2 seconds and put into position then the glue can bind and you get left with a half fitted grip. I needed to sand the inside of the grips and make my bars smooth (remove any existing residue) so the grips would slide on with a little resistance, but not be such as bastard.

    The SV650 throttle control had a lip on the inside that needed removing. Deft hand with a sharp craft knife made short and accurate work of that.

    Make sure you position the "Bulges" where the cables come out of the grips out of the way of the clutch and especially brake levers. Once the glue sets, you can't twist them into position!

    When fitting the grips with glue, twist them into position. a) it's easier and b) ensures the whole grip and bar gets coated in glue. I've fitted both sets with oxford supplied glue and no slipping.
  4. pritch's Avatar
    I usually prefer the grips to be wired through the ignition but was advised not to bother this time.
    It doesn't seem a problem, if I stop at a red light the grips switch off. Which does seem to be over egging the pudding a bit???
  5. p.dath's Avatar
    I wonder if Oxford might have been better of to make the cut off voltage adjustable. Seems to effect people differently. Some get left with a bike that can't start, and others have them turn off at red lights.
  6. mnkyboy's Avatar
    Use grip glue

    Means the grips are removable.
  7. born disturbed's Avatar
    Great write up I will use this tool to help me install my hot grips (not Oxford but a good brand anyway)
  8. Neon's Avatar
    Yeah I second the grip glue. They are not indestructable, eventually they'll wear out. Ever tried removing a set of hot grips that are superglued on? New throttle tube time... Also pays to double check clutch / brake lever and throttle movement before gluing the grips in place (you obviously did this but for those who don't think of these things...).
  9. Rogue Rider's Avatar
    Cool explanation, I decided to wire mine to the ignition so that they only work when the key is on. Had a mate who's battery kept draining and running flat and wanted an easy solution and easy use. I like the Oxford console, it fits discretely out of the way out of direct sight.
    I do like the one on my mates BMW better, the switch system is way more convenient. Just dont like BMW's lol.
  10. p.dath's Avatar
    For those of you that used the superglue that came with the grips to stick them on - I've since found out that plain acetone removes the superglue. So if you need to remove grips that have been superglued on, just squirt some acetone in. Apparently takes about 30s to break the superglue down.