RS Warrior Forum banner

Motor noise

3K views 34 replies 5 participants last post by  flyingmerkel54 
#1 ·
Hi guys, I started my bike this am and noticed a very light noise near the front of the motor it's like a soft thuding noise, hard to explain. A slight raise in rpm and it's gone. I use Mobil one synthetic v twin oil should I be using something different. I'm worried a bit about piston slap. Any ideas
 
#3 ·
Piston slap noise is similar to a rocker arm noise but deeper it is a mechanical sound. The engine needs to run for awhile to allow the pistons to heat soak & grow = the noise gradually goes away.
Do you have a breather filter on the LCV hose? If so the "thud" noise could be emanating from the filter.
 
#6 ·
There is a Yamaha Tech Bulletin from 2005 on motor noises that are incidental to the big cube beast motors in the Star lines. I cannot find it here anymore but here is a link to RS Clinic for now. I will grab a pdf off my home computer and put it into Documentation.


Here's a pdf. My Yamaha document pdf is from a multi-generation fax back in 2005. It's nearly impossible to read. If anyone has that Technical Bulletin in legible pdf I'm interested!

So this attachment was retyped by the guys at RS Clinic way back.
 

Attachments

#9 ·
Thanks for the warning, it's a grinding noise on the right side front area of the motor, starts fine but the noise gets worse when the bike is hot or warmed up, I guess I'll wait till I start to have starter problems, I'll get into the manual and see if there's an another gear in the mix that could be causing it.
 
#10 ·
Would it help to use a mechanic's stethoscope at warm idle to listen-in and locate a likely location by comparing to component locations? Just apply the tip to three different locations around where you suspect it's coming from and it can sometimes add clarity.
 
#11 ·
Hey buddy I know it's been a while since I posted this the noise is getting worse unfortunately, now of course I know you can't diagnose or fix this problem here, it's coming from the right side by the sprage hear and accompanying drive gears, it looks like the cover is removable can it be repaired without splitting the case? I have used Mobil one since I got it, maybe try something else? Or a heavier oil. Hope you are having an awesome summer brother
 
#12 ·
As you know, the anti-reversing (Sprague) assembly, sometimes called a sprague clutch, is a specific unit of assembled-gears designed to only rotate one direction. In some motorcycles it can be removed and replaced in-the-frame no need to remove the motor.

On the Warrior, the arrangement is a little different. The assembly is separated and is referred-to as the Starter Clutch. There are 6 recommended parts imo (see 5-75 items 1,2,3,4,6,7). Full job see 5-73 - 5-78.

IMO it's a mistake to selectively replace bits, they really all get beat-up. Others disagree.

The PARTS manual page C9 shows the true nature of the beast. You need items 16,17,18,19,20,21,25. You might need the 6 bolts item 22, and might need fixing bolt/washer items 24,26.

Here's the thing. Most often when this fails the motor will not start. But its robust and seldom fails (to this point in history). When the motor is running and cold I use an inexpensive mechanic's stethoscope to locate the source of the noise. If you wait until the motor is no longer running then you are shooting in the dark.

The grinding noise could be inside the starter motor. Loose magnets or failed bearings or a bad gear. So check the starter gear too (item 11) for wear or damage clues. If you replace item 11 then get items 10,12 too.

This work is not terrible on the Warrior, except you need a really-good 'holder' tool for the generator-rotor-assembly and maybe more than two hands because you need to break-loose the bolts without letting the crankshaft rotate. Plus same to hold the starter clutch from rotating while pulling those bolts.

I'm certain there are tips and tricks, but the service manual covers what looks to be all the nifty tools (based on my experience with my prior vstar1100 and othe old bikes, most of which have slightly different designs). Check page 5-76 for the holders. Sometimes I invent something from bits in the garage lol.

My worry is that you might buy all the anti-reversing parts and jump-in, only to discover the trouble is in the starter or at the primary gear behind the fixed timing wheel (other side of the generator shaft where the CPS lives). Or worse, the grinding could be crank bearings.

Mechanic's stethoscope might help you identify location of noise closely enough.

I'm certain others will chime-in too.
 
#18 ·
As you know, the anti-reversing (Sprague) assembly, sometimes called a sprague clutch, is a specific unit of assembled-gears designed to only rotate one direction. In some motorcycles it can be removed and replaced in-the-frame no need to remove the motor.

On the Warrior, the arrangement is a little different. The assembly is separated and is referred-to as the Starter Clutch. There are 6 recommended parts imo (see 5-75 items 1,2,3,4,6,7). Full job see 5-73 - 5-78.

IMO it's a mistake to selectively replace bits, they really all get beat-up. Others disagree.

The PARTS manual page C9 shows the true nature of the beast. You need items 16,17,18,19,20,21,25. You might need the 6 bolts item 22, and might need fixing bolt/washer items 24,26.

Here's the thing. Most often when this fails the motor will not start. But its robust and seldom fails (to this point in history). When the motor is running and cold I use an inexpensive mechanic's stethoscope to locate the source of the noise. If you wait until the motor is no longer running then you are shooting in the dark.

The grinding noise could be inside the starter motor. Loose magnets or failed bearings or a bad gear. So check the starter gear too (item 11) for wear or damage clues. If you replace item 11 then get items 10,12 too.

This work is not terrible on the Warrior except you really want to by a really good generator rotor assembly holder to pull the bolts without roaring the crankshaft. Plus to hold the starter clutch from rotating while pulling those bolts.

I'm certain there are tips and tricks, but the service manual covers what looks to be all the nifty tools (based on my experience with my prior vstar1100 and othe old bikes, most of which have slightly different designs). Check page 5-76 for the holders. Sometimes I invent something from bits in the garage lol.

My worry is that you might buy all the anti-reversing parts and dig-in, only to discover the trouble is in the starter or at the primary gear behind the fixed timing wheel (other side of the generator shaft where the CPS lives). Or worse, the grinding could be crank bearings.

Mechanic's stethoscope might help you identify location of noise closely enough.

I'm certain others will chime-in too.
Hi Arizona its been a while, been a dificult summer, health issues, weather, etc.
could you explain this paragraph please.

This work is not terrible on the Warrior except you really want to by a really good generator rotor assembly holder to pull the bolts without roaring the crankshaft. Plus to hold the starter clutch from rotating while pulling those bolts.

The noise has gotten pretty bad over this summer and looks like im going to have to tackle the starter clutch and all the other gears and bearings. I have not romoved the starter to check that but I dont understand why the starter would cause this noise when the bike is running.

Hope you have had a great summer so far, hoope to here from you or anyone else who wants to chime in
 
#15 ·
If the starter's driven gear is hanging up against the idlers that engage the starter clutch then you'll hear it on the right side of the bike, that is the drive gear end, and it'll still sound-off while running. If it's a magnet ripped off then it will grind inside the starter while starting, and might jam up enough to cause the gear trouble. These gear issues can vibrate enough to jar the frakking magnets off. But if it's the starter clutch you'll hear it behind the far right side because it sits behind the generator. If it's the primary gear you'll hear it on the left side. Yep that stethoscope will clear-up conditions.
 
#17 · (Edited)
+1 with Churchkey's creative troubleshooting suggestion (y) and you can bench test the starter after removal for noise and wear.

Based on your OP and recent posting I suspect the Warrior Starter Clutch components are failing.
If so you'll need to remove the Generator cover, as shown below, and possibly pull the Generator Rotor.
  • The Yamaha Factory Service Manual does an excellent job detailing the proper procedures and tools required to do the task at hand!
  • Take Note that the Starter Clutch Idle Gears 1 & 2 and their related parts will remain in the Engine Case and not as shown in the photo :)
 
#19 ·
Stumble paragraph, my bad. Now it reads:

"This work is not terrible on the Warrior, except you need a really-good 'holder' tool for the generator-rotor-assembly and maybe more than two hands because you need to break-loose the bolts without letting the crankshaft rotate. Plus same to hold the starter clutch from rotating while pulling those bolts."
 
#20 ·
Hey Arizona hope your summer has been an adventure, thanks for the above, so you know where I might get one of these holders, I see it in the service manual, maybe someone has one i can borrow??? Do you use the same tool for the starter clutch or is it two different tools?'
 
#21 ·
Check out the manual for each task. Its possible to use the rear wheel brake for part of it but it's far safer to use a tool if working alone. Or at least that's how I feel. Two different attachments. You'll see what I mean. It's not rocket science.
 
#22 ·
Well I just used the stethoscope noise is the same thought the motor, starter area as well, I started the bike and removed the starter, lots of blow by (is this normal) noise remains the same, after turning it if I reached in to the starter clutch and it works to correctly, it does have a lot of side to side movement (normal?) Or is there a thrust washer missing? I am now more mystified after using the scope.

Hey do you or anyone know where I can get this till your talking about
 
#24 ·
Separate from above:

"Well I just used the stethoscope noise is the same thought the motor, starter area as well, I started the bike and removed the starter, lots of blow by (is this normal) noise remains the same"

If the noise characteristics are the same and the volume is identical from all directions then it's very possibly crank bearings.

If the noise volume is greater from one point than any other point then identify from the motor parts views what item is closest to the location.

Here's an idea but I don't know if it will work because I never tried it. But wth right. With only the starter out, you might raise the rear wheel and have someone manually rotate the rear wheel and listen around the motor with the stethoscope. Maybe the absence of motor noise will help.
 
#25 ·
Well all I removed the clutch cover to check for anything loose in that area, all is good. So today I'm going to remove the primary Cover and see what's toyp in there. If all is well the last thing will be starter and generator cover and see what's up in there. If I find nothing I will be really surprised and confused. I have noticed the noise is very bad at slow speed start stop in town, I'll keep ya updated. I needed to change fluids anyway so not a waste of time.
 
#29 ·
There are no metal pieces on the cam cover area so it doesn't make sense
The mechanic's stethoscope seems to be unhelpful. You're at the bike and can't determine the noise source. Frustrating.

Can you post a bunch of clear YouTube videos from all angles with good sound quality 👌 maybe that will help.
Thanks I will give it a try, if someone who didn't know the bike where to ride it the noise might not be evident but I know it's there cuz she's mine and this noise is driving me nuts. Well at least the season for me if drawing to a close
The mechanic's stethoscope seems to be unhelpful. You're at the bike and can't determine the noise source. Frustrating.

Can you post a bunch of clear YouTube videos from all angles with good sound quality 👌 maybe that will help.
 
#28 ·
The mechanic's stethoscope seems to be unhelpful. You're at the bike and can't determine the noise source. Frustrating.

Can you post a bunch of clear YouTube videos from all angles with good sound quality 👌 maybe that will help.
 
#34 ·
Notice one push rod is a different length so you put it back where it goes. Notice the 'folded copper washer' step. The e-manual covers every step. It's helpful to also notice the decompression bits and lifter reinstallation oiling. The rest is just parts off parts on.
 
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top