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Discussion Starter · #1 ·
Hello everyone,

Got this 1995 Funduro. It just refuses to run smoothly at around 2500rpm. Right around where you want to do 50km/hr in fourth gear. Change down to third to increase the revs at the same speed and it's much better. Maybe I am expecting too much from a big single having another bike which is a 1400cc four cylinder which is smooth as butter in any gear at any speed. But I don't think so. I do believe this Funduro should be able to run smoothly at 2500rpm.
What I've done so far:
Cleaned twice and rebuilt the carbs with new needles and correct jets.
Checked float levels including connecting a clear tube to verify level.
Checked the choke isn't active once warmed up.
New spark plugs and leads.
Checked resistance in coils is within spec.
Checked and adjusted valve clearances
Checked the valve timing was correct
Checked and double checked there are no vacuum leaks.
New air filter.
Adjusted slow running jets for smoothest running at idle.
Dropped and raised needles one notch up and down from standard setting.

Now I am running out of ideas.
I have checked the voltage regulator and it maintains between 14 and 14.8 volts provided the lights are on. Turn the lights off and it spikes, sometimes right up to 17 volts (Yikes!).But again with the lights on, it's within a normal range. I have also tried running the bike with both plugs to the voltage regulator disconnected which has no effect on the rough running at 2500rpm.

The bike starts instantly, idles nicely and has a ton of power at wide open throttle.
What have I missed?

Pierre
Rotorua, New Zealand
 

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Hello everyone,

Got this 1995 Funduro. It just refuses to run smoothly at around 2500rpm. Right around where you want to do 50km/hr in fourth gear. Change down to third to increase the revs at the same speed and it's much better. Maybe I am expecting too much from a big single having another bike which is a 1400cc four cylinder which is smooth as butter in any gear at any speed. But I don't think so. I do believe this Funduro should be able to run smoothly at 2500rpm.
What I've done so far:
Cleaned twice and rebuilt the carbs with new needles and correct jets.
Checked float levels including connecting a clear tube to verify level.
Checked the choke isn't active once warmed up.
New spark plugs and leads.
Checked resistance in coils is within spec.
Checked and adjusted valve clearances
Checked the valve timing was correct
Checked and double checked there are no vacuum leaks.
New air filter.
Adjusted slow running jets for smoothest running at idle.
Dropped and raised needles one notch up and down from standard setting.

Now I am running out of ideas.
I have checked the voltage regulator and it maintains between 14 and 14.8 volts provided the lights are on. Turn the lights off and it spikes, sometimes right up to 17 volts (Yikes!).But again with the lights on, it's within a normal range. I have also tried running the bike with both plugs to the voltage regulator disconnected which has no effect on the rough running at 2500rpm.

The bike starts instantly, idles nicely and has a ton of power at wide open throttle.
What have I missed?

Pierre
Rotorua, New Zealand
Sounds like VR shot, should max at about 14.8 v, lights off, no other load expect ignition. Otherwise you seems to gone through everything else. Carb rubber manifold can split, check it too
 

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Discussion Starter · #3 ·
Sounds like VR shot, should max at about 14.8 v, lights off, no other load expect ignition. Otherwise you seems to gone through everything else. Carb rubber manifold can split, check it too
Thanks. I've ordered a VR. Should hopefully be here in a week or two. And hopefully that will fix the problem. Although I still fail to see how over voltage causes rough running. But fingers crossed that is the problem.
 

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Sounds like VR shot, should max at about 14.8 v, lights off, no other load expect ignition. Otherwise you seems to gone through everything else. Carb rubber manifold can split, check it too
See FAQs for others experiences of VR issues on this model. Quick check - see if runs better With lights ,heated grips ON (reduces excess voltage) before replace, also ensure battery terminals are not loose, not corroded that's another quirk with all models,
 

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also ensure battery terminals are not loose, not corroded that's another quirk with all models,
And ensure the muli-pin blocks are OK too. The size of the wiring from the VR is borderline. If the insulation is stiff, it is possible the wires have been lightly fried
 

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F650 Funduro 1998
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I am having the same problem. I replaced the cdi but that didn’t do it :mad: hope your VR will fix it. Small difference I measured the coils with cable and plugs and got near 15 khz. Manual says 6 to 13. cables and plugs measure 4.70. I will follow your progression. Good luck!
 

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Waiting for the vr fix i just went with the cheap basics and replaced spark plugs and cables and caps. Drives again
like a dream. So even though measurements seemed okay there was something wrong. I am very happy!
 
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