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Discussion Starter #1
OK, after several months with the bike off road I decided to get someone else to do the repairs. It cost me a fortune (mostly labour) but I just didn't have the time or expertise to do it myself. But it is still not right.

I thought I'd see if anyone can help me pin down the problems before I go shout at the mechanic...

The first problem occurred at around 50mph. I was happily tootling along when there was a sudden loss of power. Not a total loss - the bike was still moving but it was very gradually slowing down. When I opened the throttle there was no acceleration, the engine roared as you would expect but there was no push.

Yesterday, I had to travel from one office to another. The bike started ok and the journey took around 45 minutes but again the power loss happened this time at 70mph on the motorway. I made it to my destination but then second problem occurred. When I left the office after popping in for just 2 minutes. The bike wouldn't crank. It sounded like the battery was partially flat. At first it tried to crank but after a few tries all I got was the click of the solenoid. I rolled it down a hill and got it started and managed to get home.

When I got home I took the battery out and tested it. It showed 12.4V! If it had been dead, it couldn't have fully charged in the 1/2 hour it took to get home, right?

A little more info that might be relevant. As part of the work necessary to get the bike back on the road I have had new exhausts fitted (V&H Cruzers) and a new battery (a Yuasa YTZ14S).

I had wondered if the CCA on the new battery was a bit poor but when I looked at the Yuasa site it says 230 (which is 20 more than the YTX14AHL-BS recommeded by this site) which should be more than enough.

I am wondering if the loss of power is somehow connected to the starting problem.

Any ideas folks?
 

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Search Goddess
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The loss of power at the higher RPMs may be the hose in the right ear (if you still have the ears)
Make sure the hose is properly seated in the cover and not bottoming out. Cut the tip at a 45 degree angle to make sure.
 

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Discussion Starter #3
Thanks, I have noticed a loose hose in that vicinity. Is it a smallish hose - less than 1/2 inch diameter? How does it connect to the air filter? What is the other end attached to?
Thanks.
 

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Once Banned
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The cranking problems are somehow related to the electrical system. It may be that the battery is a wet cell, or it could be that the ground from the battery to the engine is corroded. Check the ground first, - it's the cheapest. As to the engine stall, I'm not sure what it connects to on the other end, but it just sits in a hole in the ear. This has caused a lot of members to scratch their heads wondering why the bike stalls above 50. Do make sure you cut it at a 45 before stuffing it back in the ear.
 

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Uber Member
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not what u wanna hear.... but that happened to me with my stator.....run through and do a full stator and R/R trouble shoot check with a voltmeter.... i hope its just something like a bad ignition, cause that is much easier and cheaper to replace....

on a side note to check the battery, have it load tested at any autoparts place....most do it free of charge.
 

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scot_vulcan said:
When I opened the throttle there was no acceleration, the engine roared as you would expect but there was no push.
That part bugs me. Engine roared as in revved good, but no power? Usually from what I've read when the bike stalls out at higher speed there is no revving, usually caused by wind pushing against the hose in question causing it to bottom out or something. Then not wanting to start? I'm wondering if these two things are related or not? Starting sounds like an electrical problem, but the lack of power with engine revving sounds more like clutch slippage??? Just airing some thoughts, not suggestions! Wondering if the clutch is mis-adjusted???
 

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Discussion Starter #7
fergy said:
Engine roared as in revved good, but no power?
I know it sounds wierd but that is exactly what happens. Its not a stall, the engine is still running but not putting the power down. The lack of power is only at the top end, if I stop I can pull away again no problem.

fergy said:
Starting sounds like an electrical problem, but the lack of power with engine revving sounds more like clutch slippage???
Hmm. I had considered this myself but the plates are new in last year so I had discounted it as the problem. But one of the things I asked the mechanic to do was replace the clutch cable. I will check this out.

cegodsey said:
It may be that the battery is a wet cell
I am not sure what you mean here, do you mean water in the battery or something else? I had asked the mechanic to put in a sealed gel battery and he selected a Yuasa YTZ14S. The Yuasa site isn't clear exactly what type of battery it is but it says 'valve regulated' on the battery. To fit it in the battery box though he has re-routed the wires and dropped it in on its side. he said it should work fine.
 

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I read this post earlier but got distracted when the phone rang (or wind blew its easy lol)
Fergy I totally agree with you about possible clutch slippage, not sure if anything to do with the electrical system would cause anything like that. the drive train is where to start looking
 

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Not that side, ding dong! Maybe I'm rubbing off on you as well...

If there is a vent hose on the battery, then more than likely it is a "wet" battery - you have to add water when it gets low. The numbers don't sound like a gel cell / sealed type of battery. I can tell you a good number for a Yuasa MF battery is YTX14AHL-BS.

As to the stalling problem, what kind of oil are you using? The only reason I bring this up is that we've had quite a few discussions about Energy Conserving additives, and I wonder if this might be a side effect of high rotational speeds. Is it at 70mph, specifically, or is it at 5000 rpms, in any gear?
 

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Geez, I re-read your post - the battery isn't really on it's side, is it? I don't think that will work...

OK, I looked on Yuasa's site, and here's your battery (a Maintenance Free):


Still, I don't think it will work on its side - It still has fluid in it, and the plates are oriented a certain way.
 

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Discussion Starter #12
cegodsey said:
As to the stalling problem, what kind of oil are you using? The only reason I bring this up is that we've had quite a few discussions about Energy Conserving additives, and I wonder if this might be a side effect of high rotational speeds. Is it at 70mph, specifically, or is it at 5000 rpms, in any gear?
I have only taken the bike out twice since I got it back and it happened both times at ~50mph and at ~70mph. Both times I was accelerating. I wasn't really paying attention to the revs but I was in 5th and I don't think it would rev that high in 5th at those speeds?

I am going to check out the clutch tonight (weather permitting) and I will ask the mechanic what oil he used.

cegodsey said:
Geez, I re-read your post - the battery isn't really on it's side, is it? I don't think that will work...
Yup, if you rotate your picture 90° clockwise, that is how it is fitted in. He has had to re-route the black wires to get to the terminal that is now in the bottom of the box. I have emailed Yuasa to see if it will be a problem.
 

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I could be wrong but the battery being on its side just doesn't seem good to me, the plates inside a battery are lead and they are in there from top to bottom, I would think that from normal driving and bumps and what not that those plates would end up bending and laying on top of one another, also what is filled in these batteries will no longer be on at least the top lead plate. please someone correct me if I am wrong about this
 

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and the Adventure Cycle
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If it's an AGM (Absorbed Glass Mat) battery, I don't think there'd be a problem mounted sideways.
I thought that was one of the advantages of them.

EDIT: This is from Yuasa's FAQ's.............
Can an AGM battery be installed in any position ?

In most applications, batteries are installed in an upright position, but in some situations there is a need to tilt them (sometimes at very extreme angles) or lay them completely flat on their backs.
Yuasa typically supplies AGM batteries with separate acid packs that you must fill (and charge) yourself. We do not recommend that this type of battery be installed on it's side, or even an extreme angle, due to possible leakage occuring.

Fortunately, Yuasa offers many AGM batteries as "Factory Activated". Generally this type of battery is safe to install in almost any direction. If there is any question of a particular vehicle/battery/installation please contact us for our specific recommendation before attempting to use battery.
 

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Discussion Starter #15
hyperbuzzin said:
If it's an AGM (Absorbed Glass Mat) battery, I don't think there'd be a problem mounted sideways.
I thought that was one of the advantages of them.
Yeah, looked at the Yuasa site but the battery specs aren't clear if it is just a sealed lead acid battery or a AGM type. I have emailed them and will update this thread when they reply.

Thanks guys.
 

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wow and correct me you did. Thank you Hyper I have just learned something new that I never thought was possible.
 

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Discussion Starter #17 (Edited)
OK, here is what Alan Kohler (a very helpful guy) at Yuasa says:
Putting that battery on it's side should be no problem at all. Acid is absorbed into the plates and separators on all AGM (YT, YTX, YTZ) batteries. AGM stands for Absorbed Glass Mat. Terminals take the electricity from the soaked up plates.

I would still check the voltage of the battery, and possibly do a load test. You can do a simple load test with a voltmeter, on the battery, while trying to start the bike. You should never see less than 9.5 volts, if you do, there is a problem with the battery. Make sure it is fully charged when you do this. You should also have the voltage regulator checked out. That battery needs at least 14.2 volts to charge back properly. If it has less than that, you will need to charge periodically with a charger.
So, providied that the battery is not duff, this shouldn't be the problem. I have a voltmeter but I am not an electrician. Can someone explain how I go about doing the load test (bold bit in quote) please?
 

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If I understand it correctly, you need to put your volt meter on the battery before starting. Should be around 12.5 volts. While connected, crank the starter and watch the meter. If it dips below 9.5 volts, your battery is failing under a load. Someone correct me if I'm wrong!
 

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Sounds right.

I think Fergy is probably right on all this. It sounds like you have clutch slippage, and it's more than likely caused by some mechanical issue rather than the oil. But the oil still is a possibility.

As to the battery, you can tell from the pic that it was sealed at the factory. I know my Yuasa came with the fluid, so it isn't a gas mat and must be upright. It's good to see a battery company delving into different technology.
 

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At 70 MPH the engine should be at 4500 rpm. 5000 is too high. Probably is slipping.
 
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