Heated handgrips affecting smooth running

[Oakie]

Hi. This in my work bike, a 2018 CT110 SuperCub (12 volts electrics). New last year and part of the deal was heated handgrips on it before winter. This duly happened. Trouble is though that when I turn them on, the engine speed drops to the point where it will stall eventually. Turn the grips off and it will return immediately to the sweet running beast its always been Side issue is on a day where I use them a lot, I'm using more throttle to keep it running and consequently, more gas. I have run out of gas once and gone very close two other times.

Other people's bikes with the same grips go fine. The mechanic doesn't think he can do anything about it. It is wired through the ignition.

Any thoughts?

[caseye]

Hi. This in my work bike, a 2018 CT110 SuperCub (12 volts electrics). New last year and part of the deal was heated handgrips on it before winter. This duly happened. Trouble is though that when I turn them on, the engine speed drops to the point where it will stall eventually. Turn the grips off and it will return immediately to the sweet running beast its always been Side issue is on a day where I use them a lot, I'm using more throttle to keep it running and consequently, more gas. I have run out of gas once and gone very close two other times.

Other people's bikes with the same grips go fine. The mechanic doesn't think he can do anything about it. It is wired through the ignition.

Any thoughts?

Yep, sack the mechanic and find a good auto sparky! it has to be a wire shorting somewhere. Ride on Oakie.:jerry:

[Oakie]

Yep, sack the mechanic and find a good auto sparky! it has to be a wire shorting somewhere. Ride on Oakie.:jerry:

My thought was a short somewhere but I'm not a mechanic's arsehole so haven't said much apart from pointing out the problem. To be honest, I'd be quite happy if he just hooked it up to the battery. They've got a kick start so there's a plan b if I forget and flatten the battery. Cheers

[F5 Dave]

They should be connected to the battery via a relay. A relay is a remote switch. Very cheap at auto place like repco. It caries the high current directly to the controller.

It has a sense wire that energizes when the ignition switch is turned on. Connect it to something that gets power when switch is on. Like the feed to the rear brake light switch. (One side of that switch will have power all the time the other only when you brake). That turns the relay on.

This isolates the current draw from anything critical and should solve your problem.

The only other question that is near the top of the list, is does the alternator has enough output to feed the grips?

When set up as above connect a multimeter to the battery and rev it up. Then turn the grips on. It shouldn't change much. It could be though that the output is minimal at idle and the extra draw sags the voltage. But if it is enough to charge a battery for electric start you'd think it wasn't that marginal.

Go to an auto electrician.

[Oakie]

The only other question that is near the top of the list, is does the alternator has enough output to feed the grips?


Thanks for all that. The alternator should have enough output as other bikes at work (the same model with the same grips) don't have the same problem.

[F5 Dave]

Unless you have a really sad battery it would appear some muppet installation. You'd think apprentice mechanics would have had a good grounding in electrical theory drummed into them, more so in last 30 years.

[jellywrestler]

Hi. This in my work bike, a 2018 CT110 SuperCub (12 volts electrics). New last year and part of the deal was heated handgrips on it before winter. This duly happened. Trouble is though that when I turn them on, the engine speed drops to the point where it will stall eventually. Turn the grips off and it will return immediately to the sweet running beast its always been Side issue is on a day where I use them a lot, I'm using more throttle to keep it running and consequently, more gas. I have run out of gas once and gone very close two other times.

Other people's bikes with the same grips go fine. The mechanic doesn't think he can do anything about it. It is wired through the ignition.

Any thoughts?

more throttle sounds like a health and safety issue. are they the same brand of grips as the others? a small bike will have a small output so it may be that they're overloading the system

[Oakie]

More throttle sounds like a health and safety issue. are they the same brand of grips as the others? a small bike will have a small output so it may be that they're overloading the system
Yep. Bikes and grips are identical in all respects. It is a small bike but it does have 12v electrics.

[spanner spinner]

get your mechanic to check the current draw of the heated grips, I have seen large differences in the current draw as the quality control of most heated grips isn't great. The info I can find on the net is only listing a 200 watt alternator for your bike if lights, ignition & heated grips are using more than 200w this will drop battery voltage causing the ignition module to start to drop out causing spark problems. Two easy checks are to test battery voltage with the grips off with engine running battery charging (needs to be more than 13.5 volts) then turn on the grips and see if battery voltage drops. voltage needs to remain at 13.5 volts
If the voltage doesn't drop below 13.5v it may be that the grips are connected to the ignition feed wire & it can't supply enough current, repeat tests but test at the positive & negative connections of the power feed to the heated grips. once again should not drop significantly when the grips are turned on should be at least 13 volts with the bike running.

[BMWST?]

. .....would have had a good grounding in electrical .........

I see what you did there

[Oakie]

I see what you did there bugger. I didn't.

[Oakie]

Noticed this in respect of my problem and thought it might give some of you bright sparks a new clue.

So my handgrips have four settings as normal, from 'slightly warm' through to 'f**k that's hot'. When engaging the handgrips and losing power you'd think that the higher the setting, the more power you'd lose. But NO! The opposite is true. The lowest heat setting of the four has the greatest effect on the idle speed and the higher up the scale you go, the less impact there is on idle speed. So using setting 'slightly warm', it'll idle like a bag of arseholes until it stalls in short order but in moving the steps up to the top 'f**k thats hot' setting, the idle speed gets incrimentally better. Any ideas?

[F5 Dave]

Ideas? Yes. Wire it in proper.

[Oakie]

Ideas? Yes. Wire it in proper. Yep. But I think I need to hold the mechanic's hand a bit with this one so might need more specifics. Then I might as well do his job for him.

[F5 Dave]

Read post 9 then post 4.

[neels]

Sounds like a faulty controller or something's miswired.

There will be either resistance or duty cycle control for the heat setting, sounds a bit like something is shorting the supply to ground on the lower heat settings if it has less effect when fully on.

What make of grips, maybe a wiring diagram on the interwebs that could illuminate further.....

[Oakie]

Read post 9 then post 4.

Funny. I printed both those posts out last week to wave under the mechanic's nose when he services my bike next week.

[FJRider]

So my handgrips have four settings as normal, from 'slightly warm' through to 'f**k that's hot'. When engaging the handgrips and losing power you'd think that the higher the setting, the more power you'd lose. But NO! The opposite is true. The lowest heat setting of the four has the greatest effect on the idle speed and the higher up the scale you go, the less impact there is on idle speed. So using setting 'slightly warm', it'll idle like a bag of arseholes until it stalls in short order but in moving the steps up to the top 'f**k thats hot' setting, the idle speed gets incrimentally better. Any ideas?

The higher the rpm engine is spinning at ... the higher the charging rate.

On some small motorbikes and scooters ... the headlight dim at idle. At low rpm ... there might not be enough power supplied to provide sufficient spark AND power the heated grips. The heated grips may take their requirements first. So basically ... a power supply/demand issue.


Possibly/probably ... a charging issue with the machine you're using. Especially if the other bikes that your workmates are using ... do not have this issue.

On smaller engines ... minor issues have a major impact on the performance result.

[F5 Dave]

Yep. Bikes and grips are identical in all respects. It is a small bike but it does have 12v electrics.

. . . . . .

[FJRider]

Yep. But I think I need to hold the mechanic's hand a bit with this one so might need more specifics. Then I might as well do his job for him.

The first thing to ask is ... are all the other bikes wired up the same way .. ?? I think I can recall you stating that ... on some of the other bikes ... there aren't any heated grip issues.

If this is the case (with the bikes wired up the same way) ... get the mechanic to check it's charging capability (As mentioned in my last post).