Cruise Not Holding Speed?

[Spyderguy]

I know this is probably addressed here somewhere, But I'm not finding it. New (to me) '86 Venture Royale - cruise turns on and goes through light diagnostic, hit set and the set light comes on, but won't hold speed AT ALL. Hit either brake or clutch and resume light comes on. Hit resume and nothing. Is it a vacuum leak? Vacuum pump? Pump wiring? Where should I start? Thanks

[Flyinfool]

Are you giving it enough time?

On my '88 when I engage the cruise it takes quite a while (1 to 1.5 miles) to stabilize at speed.

If I set it at 65 and release the throttle it will drop 10 - 15 mph before it starts to gradually and very gently pick up the throttle. It feels like it is programed to never make any quick throttle changes.

[Spyderguy]

It isn't a matter of stabilizing - it's just like there is no cruise - will just coast to a stop. It never picks back up - acts just like every other bike I've ridden with NO cruise.

[gscbertrand]

Check to make sure the clutch switch at the handle bar is located in the holding hole sometime they get loose and your cruise will not engage. I have fixed that little problem before with crazy glue.

[Spyderguy]

But will the set light come on and stay on if that is the problem?

[gscbertrand]

Yep.

[Spyderguy]

Checked the clutch switch. It appears to be in the proper location and the lever is depressing the switch. Are the self-canceling turn signals speed canceling or on a timer? I think I read somewhere that there was a speed sensor that canceled them? Mine cancel by time not by speed.

[Rocket]

Are the self-canceling turn signals speed canceling or on a timer? I think I read somewhere that there was a speed sensor that canceled them? Mine cancel by time not by speed.

Cancelled by a combination of time & distance since activated, both conditions must be met to self cancel.

[Spyderguy]

Thanks Rocket

[Black Owl]

One of the biggest problems with the speed control on the older scoots was excessive wear on the pivot pin in either the brake or clutch lever. The slightest vibration will disengage the speed control. Try holding/pushing outward on the levers to see if this makes any difference.

[Spyderguy]

Tried that - no difference

[Black Owl]

Okay, one other suggestion. Try cleaning the switch with a little WD40, It may be gunked up.

 

Other than that, I'm out of suggestions.

[Condor]

Check out your cruise vacume pump and look for leaks in the vacume lines.

[MiCarl]

If the SET light is coming on and staying until you cancel or use the clutch or brake it's not electrical.

 

There is a vacuum motor inside the left of the fairing that is driven by a pump inside the right of the fairing. A vacuum hose runs between them.

 

If you remove the headlight and turn signals you can get to the hose. You might as well replace it. When you replace the hose hook it to the vacuum motor first and make sure it doesn't leak (vacuum pump is handy, but I suppose you could just suck on it).

 

If that doesn't solve the problem then your issue is in the vacuum pump itself. The darn thing has 2 valves in it. One of the valves seemed not to be closing on mine until I disassembled and re-assembled it.

[Rocket]

Okay, one other suggestion. Try cleaning the switch with a little WD40, It may be gunked up.

 

Other than that, I'm out of suggestions.

 

Friesman1 had some prior issues with his, that he told me about, after I fixed it by lubing all the throttle cables (normal winter maint). This is probably, not your problem, but I thought you should be aware, that non lubed could have some affect, with some cruise control issues.

[scotty]

My guess would also be mechanical issue.

I built a cruise control test stand for final testing.

[Spyderguy]

Well, I finally got to tear into it and found the cable at the vacuum actuator was a mess. I followed it down to the junction where it makes its connection to the throttle cable and found someone had been there before me and reassembled it incorrectly. After a quick search through the manual to find the PROPER reassembly instructions, it works like new. Thanks everyone for your input!

[nascarnutt]

I did have a leak on mine, it was the hose. When I first turned on the ignition switch I could hear it sucking air. I would check the hose and the actuator diaphram also.