HES harness

[Mark K]

I'm currently in the process of rebuilding the wiring harness using BMWMick's upgrade kit. As you can see from the attached photo, the insulation was dried out and cracked, mainly near the hold-down clamp. I thought I'd put forward a yardstick to help you estimate what yours might look like. Bike is a '96 RT with milage somewhere in the low 60's. It's not blistering hot here in the summer, so I suppose it could have been worse had it come from one of our southern states.

[smiller]

And that's about a good as they get. Can range anywhere from what you experienced to the insulation literally turning to dust leaving practically bare wires. Anyone with a mid-to-high mileage 1100 should replace their HES harness.

[Steve W.]

How 'bout a 01 1150? Any HES worries?

Thanks

Steve

[smiller]

How 'bout a 01 1150? Any HES worries?

To my knowledge we haven't seen any HES harness failures in the 1150 models thus far. Could be because BMW finally caught on and upgraded the harness wiring or it could just be that the 1150 bikes are newer and thus aren't showing any problems yet, but in any event so far so good...

[CanAm76]

Mark,

Could you tell me how to purchase one of the wiring kits from BMWMick. I'm going to do a spline lube this weekend, but want to also replace the harness on my '97RT. Thanks, Ed in Geneseo, IL.

[Ken H.]

How 'bout a 01 1150? Any HES worries?

Thanks

Steve

The 1150's don't have quite the break down of wire insulation problems of the older ones, although occasional failure of the actual HES have been known. It's certainly far less of an issue though.

[AndyS]

Hi Smiller,

Unfortunately they can and do fail. My 04 has failed. The replacement from a breakers yard is working fine

Andy

[smiller]

Unfortunately they can and do fail.

I didn't mean to say that the HES never fails on the 1150, only that the problem with the harness insulation failing hasn't seemed to be a problem... but of course this might change as the bikes get older. Out of curiosity, if you know... was your failure due to a failed HES pickup or the harness insulation?

[Mark K]

Mark,

Could you tell me how to purchase one of the wiring kits from BMWMick. I'm going to do a spline lube this weekend, but want to also replace the harness on my '97RT. Thanks, Ed in Geneseo, IL.

 

I sent you a PM, Ed. Hey, is your RT Black? I may have seen you over there off of Wolf Road. Since we're reasonably close, let me know if you need any help with your upcoming operation. I've not gotten that far into the RT, but I do need to learn how to get back there -- my gearbox needs to come out for some work. At the very least, I could supervise and offer encouraging words

[bmwmick]

I'm currently in the process of rebuilding the wiring harness using BMWMick's upgrade kit. As you can see from the attached photo, the insulation was dried out and cracked, mainly near the hold-down clamp. I thought I'd put forward a yardstick to help you estimate what yours might look like. Bike is a '96 RT with milage somewhere in the low 60's. It's not blistering hot here in the summer, so I suppose it could have been worse had it come from one of our southern states.

 

Mark,

I do not believe the ambient temps have much to do with the deterioration of the insulation. More likely the number of heat events on the engine. If you have to idle a lot in traffic, it will kill the insulation sooner.

Yours was definitely 'on the edge' but I have seen a LOT worse like Seth mentions.

 

Mick

 

Ed,

I sent you an E-Mail

[bmwmick]

Ed,

Sent you an E-Mail but it bounced. Sent PM.

Mick

[HI-TECH-CHECK]

I just checked my 97 with 50k miles and it looked fine.

[bmwmick]

How did you 'check' it? The damage is INSIDE the sheath right under the upper strain relief clamp. Did you cut the sheath to look inside?

 

Mick

[AndyS]

Out of curiosity, if you know... was your failure due to a failed HES pickup or the harness insulation?

It was due to HES pickup being intermittent.

Andy

[HI-TECH-CHECK]

How did you 'check' it? The damage is INSIDE the sheath right under the upper strain relief clamp. Did you cut the sheath to look inside?

 

Mick

 

Yes I did.Wiring still flexible with no evidence of insulation cracking.

[strat]

I just did this hes upgrade and had to use some self fusing tape instead of heat shrink...anybody know the temperature range for that tape? I may be doing it again if it's not up to snuff.

 

Cheers

strat

[strat]

found out!!!! 500 degrees so I think I'm OK!

 

Cheers

strat

[gusanito]

I pulled the HES this morning and it looked fine. I cut off the shrinkwrap and sure enough, wires are all cracked, a failure waiting to happen. Bike's a '96 RT with 134k miles. Mick, I sent you a PM about your upgrade.

 

George

[smiller]

I pulled the HES this morning and it looked fine. I cut off the shrinkwrap and sure enough, wires are all cracked, a failure waiting to happen.

And that's the problem. The rest of the harness can, and often does, look perfect, so that in itself means nothing. Revealing the problem area requires removing the HES unit and cutting off the shrink wrap in the area under the clamp to the HES mounting plate, and once you've gone that far then you might as well replace the harness with some high-temp rated wire since it isn't much more work at that point. Thus the advice to just replace it and be done with it, and never have to think about it again. On most bikes of this vintage sooner or later the OEM harness will fail, most likely while in rain as many have discovered. Not fun, DAMHIK.