'84 V30 Magna - Can't get power out of it going down the road, PLEASE HELP!

[duckhtn]

I own a V30 Magna with the 500cc engine.  It has always run pretty smooth, but now I'm having issues.  When this happened it was while I was going down the road.  It was running just fine and then all of a sudden I lost power.  The ONLY way I can go down the road near highway speed is to run 3rd and 4th gear with the rpm up around 6 or 7 to keep it moving.  Well I thought maybe my plugs fowled out so I put new ones in.  NO change.  So then I checked my air filter and found a mouse nest in it.  Cleaned it out and still NO change.  Then I emptied out all the gas from both tanks thinking bad gas and put fresh back into it.  Once again, NO change.  I then sprayed out the carbs with cleaner with again, NO change.  I'm now to where I don't know what to do or what it may be.  It idles just fine but just won't rev up like normal and give me the power I always had.

PLEASE if you have an idea or know what the problem is here, HELP me out ASAP.  I have an MDA fundraiser ride coming up next week that I do every year that has over a 1000 bikes riding in the ride that I DON'T want to miss.

So again, PLEASE HELP!!  Feel free to directly email me at: gbart@mwt.net

[Magna86]

Sounds like it could be a few things. My first bet maybe a clogged carb or maybe fuel filter. Even though you spray out the carbs the jets on on or more of the carbs may have gotten clogged with something especially since you found a mouse nest in the airbox. When was the fuel filter replaced? Sometimes when they start to clog it will take power away due to fuel loss. Whats the mileage on the bike? Also to suddenly lose power while riding may me mechanically failure. You might want to check you compression on the cylinders. One of the pistons may have lost compression due to ring failure which would make the bike seem to have power loss but not necessarily run bad because the other cylinders are picking up the load. Sometimes u can't tell under the motor has a good load on it. Also check your oil for coolant because maybe you blew a head gasket. Some thoughts I hope it helps. Yes it could be the needles and diaphrams.

[duckhtn]

I should mention too that it is slow to rev up.  When at an idle I can turn the throtle and get the rpm's up, but it take a few seconds instead of the snap of the wrist as it should.  I know in the past I had to take the carbs apart and clean the needle valves and diaprams good to get them sliding decent again.  Maybe the same problem????  Fuel pump seems to be pumping out just fine.  All cylinders seem to be firing as it idles just fine.  I just can't get it to rev up and give me POWER.  Before I could go from 0 - 70 in 1/2 block or a couple of seconds, now I can't get to 70 taking all day trying.  If I go to 5th or OD it looses it's power and I'm down to a crawl and it's ready to stall out after a bit.  When I take off in 1st I really have to ride the clutch to get it going.

PLEASE HELP!!!!

[tshearer]

Start simple...Check your ground wire.

The same thing happened to me about a week ago. Since it came on so quick I had to look for the problem on the road. Went back to basics and looked for an electrical issue. Negative battery terminal was loose.
Hope others will give you more suggestions.

[duckhtn]

Just changed the oil the other day when I did all the rest of the things and the oil level was still where it's supposed to be and didn't seem to be contaminated with any coolant.  I just installed a new inline fuel filter.  I no longer have my compression tester, so I now have no way of telling without taking it to someone or buying a new tester.  Mileage I would have to say between 35,000 - 40,000.  I totaled out the front end about 4 years ago with my nuts so I have replaced the entire front end to include all the gauges.  Like a dummy, I didn't write down the difference of old and replacement speedo.

[duckhtn]

I just jump started it the other day as the battery was dead from sitting over the winter.  If any cable was loose I do believe I would of noticed that, but I will double check even though I'm almost sure that's not it. 

I do however value your input though!!  Thanks!!

[Magna86]

one trick for testing for basic compression to wad up a papertowel on stuff into the spark plug hole and crank the bike. The compression should blow the paper towel out about the same on each cylinder. If not the one that doesn't may have alittle lower compression or very little if it doesn't blow it out. Remember to try and set it up the same on each cylinder (meaning how much/hard up stuff the paper towel in)

[duckhtn]

I'll have to give that a try and see what happens.  I sure hope it's NOT a faulty cylinder as I'm NOT looking for a costy repair. 

I'm thinking it's NOT the problem as now that I think about it this happened to me before.  When it happened the last time a couple years ago I took the carbs apart and cleaned everything up good and all was better again.  At that time it was the needle valves and diaphrams sticking and not sliding up/down as they should of been.  That's such a pain in the butt to do though as I leave them attached to the cables because I don't want to mess up the scyronizining(spelling?) of them.  Maybe I should do again????

[Charles S Otwell]

Sound like the slider diaphragms are bad.

[Magnum Magna]

I just jump started it the other day as the battery was dead from sitting over the winter. 
I do however value your input though!!  Thanks!!

I am not sure of the effects from jumping a bike from a running vehicle I just know it is bad.  It will damage something, battery, stator or regulator I don't know.  Can you check your voltages with the bike off, idling and 3000 RPM.  It should be around 12 volts off and around 14 running.

[Greg Cothern]

I would highly suspect fuel delivery issue, especially with the mouse nest!  It could have sucked something into the carbs and clogged up a fuel passage or jet.
Try pulling the choke while riding to see if it picks up..  If so then you more than likely need to clean the carbs.  Might try some Seafoam at about double strength for a tank.

[John Luttrell]

I believe Greg hit the nail on the head; I too have seen this caused by a clogged return port in the Master Cylinder.

[John Luttrell]

Let this be a lesson to all of you not to try and answer tech questions on this board while at the same time inputting oil well production on another computer.

[dgc67]

LOL.  Yeah, last time my Master cylinder had a clogged port my bike kept getting faster instead of slowing down.

[duckhtn]

I haven't had a chance to work on this as of yet, but I'm guessing that "Greg" you may be right.  I was just hoping that I would be taking the carbs apart again as I had to a couple of years ago when it happened.  Not a bad job considering some others, but a big pain in the butt no matter how one looks at it.  Hopefully I can find the time in the next few days.