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loss of power @ 4k rpm


matthew b

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Hey

 

So basically @ 3200 and like 3950-4200 rpm typicially in 2nd gear if i hold the throttle steady I hear the engine kind of hesitate / lose power and ride choppy

 

If I give her more gas its fine or engine brake a bit....

 

I took it to the shop, they blead out the transmission (unrelated issue) , replaced spark plugs, (which they said 1 of them was not making full contact / wire was bad or something)

 

and I got it back a week later.... its doing the same damn thing again at 4k rpm's and I have no idea whats going on

 

 

I think it only happens at regular temp, not when its first running a bit cold so they prob couldn't re-produce it...

 

if im going up a steep hill in san francisco it is much more noticeable.... also, when I rev the engine 50% of the time its fine, 50% of the time it kind of hiccups when I rev it..... the guy before me spend 1200+ on electrical repairs and Im wondering if its electic issue with relays or something more serious... should I bring it back to that shop?

 

Anyone else have this issue?

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I'm no mechanic, but the first thing I'd do is try to track down EXACTLY what electrical work the previous owner spent $1,200 on. Get a copy of his invoice if you can - he may have done some remapping of the EFI. Maybe he had an aftermarket exhaust that he mapped for, put the stockers on before he sold it back to you, and never changed the computer settings.

 

Common guys - somebody else out there must have a better insight into this owner's problem - and it's a hell of a lot more important than searching the net for a pewter belt buckle!

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Guest ratchethack
Common guys - somebody else out there must have a better insight into this owner's problem - and it's a hell of a lot more important than searching the net for a pewter belt buckle!

I'd be pleased to help if I could. But without lots more and lots better starting info, so far we got naught but one great big potential hair ball of unlimited dimensions here. :o

 

You have to make so many assumptons just to get started here that just about anything anyone can say won't be of any value. It could be a horrific Gordian knot of multiply-interdependent contributing factors, or it could be one simple thing. :huh2:

 

For starters:

 

If I recall, Matt took it to Munroe? Those guys had a solid rep. when I lived in SF, but that was many many moons ago. I have no idea what $1200 in "electrical repairs" means, but if the boys at Munroe are still as competent with Guzzi's as they used to be and can't figure it out with both the work order history and the bike in hand, it'd be relatively tough to do a proper diagnosis over the Web. :huh2:

 

Was the bike ever mapped? How?

 

What list of mods? What work was done exactly?

 

I reckon if you get quality responses in direct proportion to the quality of info provided.

 

Always more'n pleased to help, but anyone here needs SOMETHING to work with!! :huh2:

 

FWIW, not sure if it's "Kosher", but troubleshooting stuff like this usually gets most play on the Tech Forum.

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Go for the simplest possible solution: bad battery connection that somehow resonates like a violin bow at 4K RPM and causes momentary loss of contact.

 

Or the most unlikely solution: a horribly bad map at 4K (very unlikely).

 

At any rate, you are NOT imagining this problem. Stay tuned, someone here will have useful advice. In the meantime, please check your battery's terminal connections.

 

I also wonder if the spark plug wires (I forget the official term) might be bad on one side.

 

Bob

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OK

 

sorry for lack of info

 

1. the bike has an after market exhaust but it has for 3+ years (i have owned it for ~3 months) and he never mentioned this issue

 

 

 

++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++

1 timing sensor $137

1 0ring $2

1 potentiometer $329

2 spark plugs $5

1 fuel filter $76

1 regulator $249

1v/c gasket $5

1 used fuel pump $312

total $1115

 

2.5 labor = $245

 

 

So this is what he had done with these notes

 

"we replaced your throttle position sense which made the bike run better, the crankshaft position sensor was also suspect and as been replaced. your charging system was not working until we put a new voltage regulator...at this point he bike was running well and charging and the fuel pump went bad and was replaced.

 

50 mile road test and it was running fine..............................

++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++

 

 

DO you think it is still some ligering issue? What should I have them look @ / do?

 

Thank you all for your time/ input / knowlege and support.

 

Cheers!

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1 timing sensor $137

1 0ring $2

1 potentiometer $329

2 spark plugs $5

1 fuel filter $76

1 regulator $249

1v/c gasket $5

1 used fuel pump $312

total $1115

 

2.5 labor = $245

 

 

 

 

"we replaced your throttle position sense which made the bike run better, the crankshaft position sensor was also suspect and as been replaced. your charging system was not working until we put a new voltage regulator...at this point he bike was running well and charging and the fuel pump went bad and was replaced.

if this is a V11 it doesn't even have a crank sensor! maybe they changed the cam sensor? and I see they got him a TPS for 329. surely all those things together were not the problem, one of them maybe. FYI, you can get a better regulator from the aftermarket for less $.. and 32.00 Harley TPS will work..

My V11 sometimes stumbles around 4200 rpm and does not like to cruse along steady in the range. I change the TPS and it got slightly better. someone told me that is the nature of the bike w/stock crossover. I plan to try smoothing it out some with a fine tuning of the TPS and redo the valve settings this spring.

Have you looked at the relays? probably not related but funnier things have happened w/the stock Seimans relays, get a set of replacements from DPGUzzi.com for less than 20 bucks, if you still have the seimans try something else.

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Guest ratchethack

OK, this is helpful info, Matt.

 

It'd be important to know how many miles on the bike, and if known, when the valves were last set, and to what specs. Should be at least 4/6 thou in/ex "World Spec", or 6/8 (my "hot weather" choice for 6 years), or Pete's personal rec., 5/7 thou. By my experience with your exact model Guzzi, the manual "book" specs for US-issue bikes, 2/4 thou, would without any question contribute substantially to the symptoms you describle, and this is often the setting that many shops use, since it's "by the book". I'd nail this one down PDQ.

 

Again, per my post above, it would be helpful to know if the bike has been mapped before or after the aftermarket exhaust was installed, whether or not it has an other than OE air filter or pod filters eliminating the airbox (also if before or after it was mapped), wheter or not it has a PC III installed, and if a custom map was done on a dyno, or a "library" map was loaded. But let's take a whack with wot we got so far.

1. the bike has an after market exhaust but it has for 3+ years (i have owned it for ~3 months) and he never mentioned this issue

May I suggest that wot the PO never mentioned is not helpful to consider here, and no assumptions of any kind should be made accordingly. If you test rode the bike before buying and got it up to full operating temp in the process, did you notice the driveability symptoms at that time?

So this is what he had done with these notes

 

"we replaced your throttle position sense which made the bike run better, the crankshaft position sensor was also suspect and as been replaced. your charging system was not working until we put a new voltage regulator...at this point he bike was running well and charging and the fuel pump went bad and was replaced.

 

50 mile road test and it was running fine..............................

I'm with Fotoguzzi on the "crankshaft position sensor" thing. This would make me suspicious about whoever wrote it up, since the bike has no crank position sensor, but he obviously meant the hall effect timing sensor on the cam chain wheel, since he replaced it, so let's give him the benefit of the doubt, assume a simple mistake in terminology, and throw that suspicion out.

 

Referring back to your description of the symptoms,

. . .basically @ 3200 and like 3950-4200 rpm typicially in 2nd gear if i hold the throttle steady I hear the engine kind of hesitate / lose power and ride choppy

 

If I give her more gas its fine or engine brake a bit....

 

. . .I think it only happens at regular temp, not when its first running a bit cold so they prob couldn't re-produce it...

 

if im going up a steep hill in san francisco it is much more noticeable.... also, when I rev the engine 50% of the time its fine, 50% of the time it kind of hiccups when I rev it.....

Coupla things.

 

The torque curve on the bone-stock 2000 Sport has a characteristic "dip" at 4500 RPM that starts ~4000 RPM. To a significant degree, this is an "inherent" attribute of the torque delivery of the motor.

 

Strangely and coincidentally enough, your account of the symptoms -- particularly your reference to it only happening at full operating temp -- bears an uncanny resemblance to the symptoms I've observed lately whilst futzing around with swapping out temp sensor holders, per current thread now underway on the Tech Forum. Assuming the bike still has the OE black plastic temp sensor holder (located on the inboard rear of the right cylinder), per recommendation of Greg Field and many others, it might make sense to pull off the blue AMP connector and VERY CAREFULLY unscrew the sensor from the plastic holder, apply a dollop of thermo-conductive paste to the tip of the sensor, and CAREFULLY seat it back in there (under VERY LOW torque -- just "slightly snug" -- no need for anything more than this!) and see if this makes any improvement. Trying this will set you back the cost of a tube of thermo-paste, and there's no down-side risk (if you're CAREFUL!) With gentle handling, you CAN (I'm here to tell you from personal experience) remove and re-install the RELATIVELY FRAGILE plastic holder underneath the sensor itself multiple times without breaking it. If it makes things worse, simply remove the sensor and holder, clean out the thermo-goop, and re-install. But no need to tempt fate if not needed! These things can and do break very easily without proper awareness and due care. Make sure to bring it up to full operating temp when testing.

 

That's about all I got for now. If you're interested, answer my Q's above, respond to some o' the ideas, and I'll give it another shot, along with the rest o' the crew.

 

I applaud your apparent interest in getting more pro-actively involved with the bike and would further encourage you to learn how the bike works as you learn how to do things yourself. IMHO, if you can ride it, you can service and maintain it. IMHO (Part II), it's the only avenue open to you that gives you a reasonable probability of being a long-term happy owner of a smooth-running, reliable Guzzi. :bike:

 

But o' course, that's just me. -_-

 

Good luck. :luigi:

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Matthew-

 

When the bike is set up properly the "dip" that we talk about with this engine is more of a stutter or a momentary hesitation. It sounds like you are experiencing more than that. My "dip" happens at more like 3100 RPM but it is very slight.

 

Pls make sure you are running with high Octane fuel of course.

 

It might be useful to have another V11 rider in the Bay area come have a look or ride your bike around when the engine is warm - just a thought.

 

Bob

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I would also describe it as a slight shutter/hesitation... It kind of feels like it is not firing on both cylinders when I keep the throttle at 4k rpm (kind of a hollow sound from the engine). Not that I wont get up a hill but I dont think I should have to give it more gas or change gears to get it up hills. other rpm's are fine.

 

 

I am not sure about valve settings...Is it going to take them any significant period of time for them to check? its $100 an hr at Munroe.... Will they be insulted to check the relays?? They replaced them a couple months ago.Instruct them to have it re-checked?

 

As far as the mapping of the exhaust, I suppose I could have them re-map it but It seems like its a bit bigger of an issue then that.

 

 

I just feel kind of bad telling them what to do since they did a lot of work on this thing twice and the issue remains. Is that all they should check? Do you think they will bill me to look into these things? I dont think they should charge me since this last time nothing was fixed.

 

Thanks again

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checking your valve gap is the simplest of tasks and YOU CAN DO IT YOURSELF! all you need is a hex wrench and a feeler gauge.

 

http://www.guzzitech.com/Valveadjust-terry.html

 

http://www.guzzitech.com/tdc-tracy.html

 

here's pics,

http://www.kodakgallery.com/Slideshow.jsp?...mp;conn_speed=1

 

oh yea, you need a 11mm box end wrench and a vise grips or small crescent wrench. you don't need the big socket on the crank nut. you can rotate the motor by turning the rear wheel in a high gear.

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checking your valve gap is the simplest of tasks and YOU CAN DO IT YOURSELF! all you need is a hex wrench and a feeler gauge.

 

http://www.guzzitech.com/Valveadjust-terry.html

 

http://www.guzzitech.com/tdc-tracy.html

 

here's pics,

http://www.kodakgallery.com/Slideshow.jsp?...mp;conn_speed=1

 

oh yea, you need a 11mm box end wrench and a vise grips or small crescent wrench. you don't need the big socket on the crank nut. you can rotate the motor by turning the rear wheel in a high gear.

 

And besides the valves, there's also Ratchet's experience with a soggy cam chain tensioner. How many miles are on this steed?

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Guest ratchethack
And besides the valves, there's also Ratchet's experience with a soggy cam chain tensioner. . .

Matt's symptoms don't line up, Skeeve. The limp-noodle OE cam chain tensioner symptoms of random miss (diagnosed by intermittent signal scatter on a timing strobe in the advance direction ONLY) are relatively minor compared to Matt's description, and show up only at idle and off-idle, never under acceleration or load at any RPM. :helmet:

 

Methinks Matt may very well be at the Classic Guzzi Newbie personal crossroads here. He either learns enough about simple 4-stroke engine theory and mechanics to acquire some tools and become halfway competent at doing his own diagnostics and maintenance (the V11 being one o' the World's Easiest moto's to learn and work on) -- or he at least learns enough to be able to communicate effectively with a shop that can do part, most, or all of it for him, or he'll soon be mired in the depths o' the ol' Swamps o' Frustration, Ignorance, and Misunderstanding, at which point it'll be time to trade The Guzzi off for a Japper moto-appliance, where he can more easily and effectively t'row the entire personal involvement part of the responsibility of ownership over the fence to a service shop, and just ride it. :huh2:

 

We're on your side here, Matt. Just trying to "Goose" you with a little prodding and encouragement, my friend. Other than a competent shop that can actually diagnose stuff hands-on, you won't learn more, nor get better advice than on this here Forum -- with the possible exception of Your Humble Servant, of course. -_-

 

"When the student is ready, the teacher appears." - Siddhartha Gautama Buddha, from the Dhammapada, circa 500 B.C.

 

Good luck, wotever you do. :thumbsup:

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Sounds like she's a bit lean in that range to me.

Pretty tough to diagnose such things online, hence all the speculation. Don't be overwhelmed by all the talk of relays & sensors. You can swap out all of the relays for very little money but I highly doubt it is your trouble. I'd start with the basics like others have mentioned, primarily valve adjust and TB sync. Leave your TPS alone unless you think someone has played with it (screws have yellow paint on them so it is easy to see) If you start changing things like that setting you are just as likely to create more trouble for yourself.

It is possible that the aftermarket cans exacerbated an already lean range. A PC3 with a proper map and perhaps a crossover will likely solve the issue. (did for me)

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The relays are in plain view under the seat. It is a good idea to keep spares around as a failure in some of these can stop the bike dead. If you pull the seat and see five little relays in a row and any of them say "Siemens" on them, replace them as soon as possible. Otherwise, it is just a matter of good practice to keep spares of those around. The ones from DPGuzzi.com have a lot of research into what would work best, the stock Siemens ones do not and WILL fail. But that is just good general practice. I don't think it applies to your running issue. That sounds like a case of the bike being a bit lean at that rpm and throttle postion. It could be a stock map (they are lean at the bottom and too rich at the top stock) or one custom made for your bike (just because its a custom map does not mean it is perfect), either way those symptoms are typical of being lean. It could also be a tps issue, particularly since they pulled the old one out. If they did not set the new one up quite right while installing it that could be it. A mis-set tps, along with out of sync throttle bodies, is likely to be more of an issue at smaller throttle openings and go away as the throttle is opened farther.

As others mentioned, I would suggest you learn to work on the bike yourself. Guzzis are reliable bikes but they do tend to have certain flaws that need to be worked out and it can be expensive and difficult to have this done by others. Often it takes a more intimate knowledge of the bike and what it is doing to correct these issue then a mechanic is likely to have. Not saying it cannot be done, just that paying others to fix the bike can be the harder more expensive way.

If I where you I would, in order, check the valve clearances, check the TB sync (or pay someone to, that is much harder then the valves and you need special tools), check and set if needed the TPS (there is a range for this setting and room for adjusting, small changes can make a difference in how the bike runs). If none of that works, I would start to consider getting a PowerCommander or other such tuning aid to correct the issue.

Good luck and keep at it. Once sorted these bike are some of the most rewarding bikes out there.

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The relays are in plain view under the seat. It is a good idea to keep spares around as a failure in some of these can stop the bike dead. If you pull the seat and see five little relays in a row and any of them say "Siemens" on them, replace them as soon as possible. Otherwise, it is just a matter of good practice to keep spares of those around. The ones from DPGuzzi.com have a lot of research into what would work best, the stock Siemens ones do not and WILL fail. But that is just good general practice. I don't think it applies to your running issue. That sounds like a case of the bike being a bit lean at that rpm and throttle postion. It could be a stock map (they are lean at the bottom and too rich at the top stock) or one custom made for your bike (just because its a custom map does not mean it is perfect), either way those symptoms are typical of being lean. It could also be a tps issue, particularly since they pulled the old one out. If they did not set the new one up quite right while installing it that could be it. A mis-set tps, along with out of sync throttle bodies, is likely to be more of an issue at smaller throttle openings and go away as the throttle is opened farther.

As others mentioned, I would suggest you learn to work on the bike yourself. Guzzis are reliable bikes but they do tend to have certain flaws that need to be worked out and it can be expensive and difficult to have this done by others. Often it takes a more intimate knowledge of the bike and what it is doing to correct these issue then a mechanic is likely to have. Not saying it cannot be done, just that paying others to fix the bike can be the harder more expensive way.

If I where you I would, in order, check the valve clearances, check the TB sync (or pay someone to, that is much harder then the valves and you need special tools), check and set if needed the TPS (there is a range for this setting and room for adjusting, small changes can make a difference in how the bike runs). If none of that works, I would start to consider getting a PowerCommander or other such tuning aid to correct the issue.

Good luck and keep at it. Once sorted these bike are some of the most rewarding bikes out there.

 

 

I doubt its the relays these were a 2000 V11 issue. Although pulling them out and cleaning the contacts will do no harm the relays usually also cause a start/not start problem rather than rough running. It was this model that was a bit notorious for crap running from the factory (not as bad as the carbed bike though) to the point Cliff Jeffieries decided to build his own ECU which works well buy all accounts. You could also try and track down a different Eprom chip the Termi version "2" didn't seem to be too bad, it looks like the shop has probally gone through most of the potential culprits anyway TPS etc etc.

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