Hot Grips Model 401 Installation and Review

By Frank L. "Cranky Frankie" Palmeri

From: Frank Palmeri <>
Date: 4/15/2004 6:56 AM

I was standing at the parts counter of my local BMW shop and noticed a package with the label "Hot Grips" hanging on the pegboard. I asked what they were and was told they were an aftermarket heated grip that cost approximately 1/3 the price of BMW accessory heated grips. I've been seriously involved with motorcycles for around 25 years but don't recall ever having seen an ad or read a review of these grips, but I thought they'd make a nice addition to my wife's K75 ("girls get cold" is how she puts it) so I bought them.

I generally do my own motorcycle maintenance, but out of curiosity I asked what it would cost to have the shop install the grips. I was told they got 3 hours of labor for the installation. Wow, that seemed like a lot of (expensive) labor to just install a pair of handlebar grips. Since it was late in the year I figured if I allowed myself plenty of time I could easily have the bike ready for spring, so I decided to do the installation myself.

I got the model 401 Universal Street grips (you can see all the grip styles at They appeared to be well made but when I attempted a trial fitting on the K75 the first problem surfaced. The clutch side grip was totally loose on the handlebar. There was no contact with the bar at all. Conversely, the throttle side grip would not go on at all. Hmmm.

The grips came with 2 pages of instructions. Apparently these grips can expand when the heating function is activated, so the recommendation is to epoxy the grips to the handlebar with a slow setting 2-part epoxy like JB Weld. That would take care of the loose clutch side grip. For the throttle side, it said if the fit was "tight" you had to sand down the throttle sleeve until the grip fit smoothly. Since my grip would not even fit on the throttle slide, this meant I was in for a lot of sanding.

I obtained a long, narrow #60 strip of sandpaper, and proceeded to run this coarse material up and down the K75's plastic throttle slide. I wound up having to remove a lot of material, producing a large pile of plastic shavings on the garage floor. Finally, I got it turned down enough to where the Hot Grip could be slid on to the throttle with only hand force.

So now it was time for the epoxy. The instructions said to apply the epoxy to both the handlebar (clutch side), throttle sleeve (throttle side) AND to the inside of the hot grips. Now here is where I had a "disconnect." I've worked with JB Weld for years and I know that once it sets up it's like concrete. I knew I'd have to put it on a little thick on the clutch side, since the Hot Grip on that side was so large it was spinning on the handlebar. But the throttle side was such a tight fit, even with all the sanding, that I questioned what would happen to the excess epoxy as I slid the grip on. The instructions said, if your throttle was the kind that had an open handlebar end (like the K75's) to place a piece of duct tape over the throttle opening to keep any excess epoxy out of that critical area.

Now, there are 2 kinds of people in the world, those that follow product installation instructions and those that don't. I have many friends who never look at a manual for any product they buy, or do so as a last resort only if all other attempts to get the product to work fail. I, on the other hand, have a different opinion. I figure that the manufacturer wants me to be successful in using their product for at least 4 reasons: it saves them a trouble call from me, it builds goodwill for them, it increases the chance I'll buy from them again, and it increases the chance that I'll tell others good things about their product. Believing this, one would then logically determine that if the manufacture took the time to include detailed, well written instructions (as HotGrips did), that it would be to one's benefit to follow them to the letter. In this case, however, this proved to be my downfall.

Intuitively, I knew that the throttle grip was very tight on the throttle, even after all the filing. I figured that this would create a pressure on the epoxy as I slid the grip forward, and that any epoxy trapped in the end of the grip would press into the handlebar end area, right where the throttle slide meets the hollow handlebar end. I knew there was no way a piece of duct tape could seal that gap against this pressure, but that's what the instructions said to do.

I mixed up the JB Weld and applied it to the clutch side handlebar. Then I used a popsicle stick to apply the epoxy to the inside of the clutch Hot Grip and slid it on. No problems there. I did the same on the throttle side, but here, they tell you to pull the Hot Grip off after sliding it on part way to "wipe off any excess epoxy." I did this but was still concerned about the epoxy that would be buried deep in the Hot Grip as I did the final installation. In any case, I had both grips on and I decided to wait 24 hours to let the epoxy set up.

When I went to the garage the next night I grabbed the clutch side Hot Grip and it was solid as a rock. The JB Weld had done a nice job of filling that loose gap. Then I went to twist the throttle side Hot Grip and my worst fear became a reality: the throttle on my wife's beautiful sparkling red K75 was welded shut.

So much for following instructions!

Not knowing what else to do, I pulled and pushed, pulled and pushed, pulled and pushed on the stuck throttle, until I was able to break it loose. Now I had a throttle that moved again, but one that would not spring closed like it was supposed to. Obviously, I had JB Weld in a place where it wasn't supposed to be, and that wasn't good.

I went to and found a customer support email address. I fired off a note describing the problem and asking for help. The very next morning I had a return message back from them asking for more information and warning me to not ride the bike in this condition. As frustrating as this problem was, it was good to know I was dealing with a company that was willing to stand behind it's product. I sent them another detailed note describing everything that happened, and while waiting for their follow-up I decided to take some action.

I disassembled the BMW throttle housing and attempted to remove the throttle, but it was stuck on solid. I could tell that there was no excess JB Weld on the master cylinder side (where the Hot Grips tech rep told me to check) so I knew it was buried in the end of the grip. So, with no other recourse, I drilled a big hole in the end of the Hot Grip. Right away I could see the entire area was caked full of excess JB Weld. There was about a 3/8 inch gap between the handlebar end and the inside end of the Hot Grip, and this is the area that was gunked up. I'd left a gap when I installed the grip because I wanted space on the master cylinder side of the throttle in case I wanted to install a throttle lock type cruise control in the future. Good thing I did, because if I'd jammed it up tight I'd have had no room to work.

Using a small pick I began the long process of chipping out the excess JB Weld. If you've worked with this product before you know how hard it is when it sets up, so it took me quite a long time to get the bulk of it out. Once I did I tried pulling on the grip and this time I was able to yank it off. That's when I could see just how far the JB Weld hand slid up into the tight, narrow gap between the throttle and handlebar - a good inch. Ouch. I finished cleaning that mess up, applied some grease, and finally I had a properly operating throttle again, albeit a brand new one with a big hole in the end.

At this point I probably had a good 4 hours invested in this project, and I hadn't even begun on the wiring yet. I was wishing I'd taken up the shop on their 3 hour installation offer. Still, it's all a learning experience, which is a good thing.

For the wiring you are instructed to find a switched hot lead to tap into. This way the grips cannot be turned on or left on while the bike is not running. I checked the wiring diagram for the K75 and it showed that BMW had provided a built-in take-off point for installing their accessory heated grips. While this was good in the sense that I had located an appropriate wire, it was bad because I did not have a male plug to install into the female plug that was preinstalled on the harness (and BMW doesn't sell the plugs separately). So I cut a little bit off of the harness wrapping tape, and after cutting off the BMW female plug I had maybe 1 inch of wire to work with. I carefully stripped off the insulation and was able to solder a fused pigtail to this tiny wire. By tiny I mean not only small in length but small in gauge as well - this wire was only a 22 gauge, while the wire in the Hot Grips kit is 18. At first I wondered why BMW used such a small gauge of wire for it's accessory grip take-off plug, but then I realized that it only runs maybe 12 inches to the fuse box. Perhaps for that short a run 22 gauge wire is all you need.

After that I had to find a spot to mount the Hot Grips resistor. This resistor is what gives the grips the Hi-Lo heat option. On Hi the grips get a full 12 volts, but on low the power is routed to the resistor first, so you need to mount it in a place where it can shed some heat. I chose to mount it on a home made metal bracket right next to the horn, under the radiator, where it would be out in the open. Then I had to mount the Hot Grips toggle switch. On K75s the top triple clamps are covered by a black neoprene pad that houses the ignition switch and 4 accessory switches. On my wife's K75 the left most accessory switch is for emergency flashers, but the other 3 are non-functional, and hold black plastic dummy switch covers. These have a habit of falling out, so I'd previously ordered a few extra ones just to be safe. I drilled a hole in one of the extra ones and mounted the Hot Grips switch into it. Then I used JB weld to glue the plastic switch into the black cover pad.

I wired everything up per the Hot Grips instruction sheet, using soldered joints everywhere (except at the switch) per their recommendation, and turned the switch on. Sure enough, the grips started to warm up, so I knew everything was working. I put the gas tank back on, cleaned up the wiring, and finally I was done. Whew.

The next day I took the bike for a test ride, and immediately discovered another problem. The instructions tell you to mount the throttle side grip in such a way that the wire for it will not bind on anything during the throttle's full range of normal rotation. In my case I mounted it such that, with the throttle wide open, the wire would just be below the point where the brake lever would be if you squeezed it full on. This would be the optimum position on any bike except BMW because, unlike every other motorcycle manufacturer, they choose to have the right turn signal button be integrated with the right side master cylinder housing. Since the K75 is my wife's bike I didn't realize this until I took it out for a ride; the Hot Grip wire is right in the way of your right thumb when you attempt to use the right hand turn signal. Because of BMWs clever cam and gear throttle mechanism I think I can move the grip position without disturbing the glued on grip if I want to, but the only way to have the wire clear your thumb for the right hand turn switch and still be free of the brake lever is to have the wire be pointing somewhere at the top of the grip, and I don't want to do that for aesthetic reasons. I guess we'll just have to live with it this way. Hopefully, it will be nothing more than a thumb-exercise providing minor annoyance.

The rest of the test ride proved to be very interesting. I've been riding for about 25 years and have never used heated clothing of any kind. I have a pair of Harley Davidson gauntlet gloves that my wife gave me that are thin enough to wear in the summer, yet warm enough to provide good protection on all but the coldest days. The outside temperature was about 45F on my test ride, and I felt fine before switching on the grips. Then I turned them on Hi and gradually they warmed up. I was curious to see how hot they would get. Would it be burning hot like an exposed steam pipe in a hot water heating system? No, they don't get that hot, but even through my leather gloves I could feel the warmth coming through. I then turned them on Lo, and still the grips were warm. At this point I parked the idling motorcycle to get off and feel the resistor, so I could see if it was heating up to make sure I had it wired in right. It had only a slight warmth to it, which is to be expected because it was a cold day and I had it mounted basically in the cooling stream.

So I got back on the bike, with the grips still on Lo, and then switch them off. Ho-boy! Even though it never felt like they'd gotten that hot, once they're off you really miss them. Guys I know who have BMWs with heated grips have always told me that once you have them you'll never want to ride without them, and now I think I know what they mean. You just have to experience it for yourself before it really sinks in.

During the whole installation fiasco I had a running email dialog with the folks at Hot Grips. As you can imagine I was not happy with included written instructions that led me to glue my wife's throttle shut. Here are the highlights from these communications:

To sum up, here's my overall impression of Hot Grips model 401:


These grips appear to be an excellent value.


Inadequate and misleading; the part about putting epoxy on the inside of the throttle grip is clearly an error, and for BMW owners they should warn you about putting the wire in the way of the right turn signal switch. The instructions for the model 401 are being rewritten but there will still be some in dealer's inventory that have not been updated.


A dash-mounted LED indicator might be a nice addition to remind you that the grips are on. You could even get fancy and add a red one for Hi and a green one for Lo.


You better be sure you're happy with your handlebars, because it will be tough to change them after installing Hot Grips. The only practical way to remove the grips after the epoxy sets is to cut them off.


I fear that my BMW riding buddies may have been right all along; once you ride with heated grips you will want them on your own bike. I'll be adding a pair to my own bike as well.

Finally, it is reassuring to know that Hot Grips stands behind their product. They were always available via email technical support, have an extensive FAQ ( Freqently Asked Questions) list on their web site (, and did send me a replacement throttle grip free of charge. It is truly refreshing to deal with a company that stands behind their product in this way.

Frank L. "Cranky Frankie" Palmeri
Guilderland, NY

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