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Discussion Starter · #1 ·
Hi peeps, your thoughts and suggestions on this. Out on a ride today, 15 miles in, I hear a strange knocking noise from the left side of the engine. Pulled over at once and killed the engine. Now when I attempt to start, something makes a spinning/whining noise but doesn't want to fire up! Any ideas or suggestions on areas to look at please?

Thanks

Pierre
 

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Discussion Starter · #2 ·
Follow up, battery on charge, seems to make all the normal noises when I turn it on, still making a whining spinney noise but no engine engagement.... Nothing throwing up on tunecu either...
 

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Discussion Starter · #4 ·
Sounds like maybe z25 gear/shaft. if you remove the alternator and check that the shaft cannot be turned too easily, or remove clutch cover and check at that end. Or it could be a sprag clutch issue but I wouldn’t have thought there would be any noise.
Thanks Gbo, I'm going to have a look tomorrow, looks like alternator looks straightforward to remove, see what I find, hopefully not lots of broken bits!

Pierre
 

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Discussion Starter · #7 ·
If the gear on the rear of the clutch has survived and you can retrieve the parts it will just be the z25 shaft and gear plus locking bolt and Belleville washer that needs replaced.
The gear looks OK although it's completely free from the shaft, looks like a fun few hours coming up!

Pierre
 

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Discussion Starter · #13 ·
Stange question coming up, has anyone had a new z25 bolt sheer? just having a quick look at the parts from Rick67 and the one currently in the bike (in bits) looks like a uprated one with belleville washer?

Pierre
 

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Discussion Starter · #15 ·
Don’t think the new type m10 bolt with Belleville washer normally shears they can come loose though.The main problem is the shaft shears as yours has, the shaft is under heavy load during start up.
Ah, so the one currenly in there was with a belleville washer, so would it be fair to say that its been upgraded in the past? when I took the retaining bolt off from the alternator side, i could do that with just my fingers and there was no evidence of threadlock compound on it at all! fair to say bolts worked loose, shaft moving while engine was running and banging about which caused to shear?

Pierre
 

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Discussion Starter · #17 ·
I’d say they would all come loose without Loctite added . Weather it’s the updated shaft or the original version.
Even the new updated ones will work loose without it and that is probably why yours snapped as the shaft end migrates towards the clutch and the drive gear on the outside. The clutch starts to chew it up as well as putting pressure on the shaft. Possibly causing it to snap , twist , bend ect .
Got it, make sense, looks like whoever did the job previous didnt do it very well!

Pierre
 

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Discussion Starter · #22 ·
I've had a look at both the Tornado (p 204) and the RS (p210) workshop manuals and I can't see any reference to Loctite use with the M10 alternator drive shaft bolt. The TreK 1130 WS Manual specifies Arexons 56A48, which is an extremely strong thread locker. I assume similar to Loctite 263 or 271. Both you can unscrew with difficulty on a large bolt. If you used 648, expect to need heat to weaken the joint. 648 is a shaft lock. Use it on the clutch nut and you'll need a breaker bar to remove the nut. That is a big thread though, so a breaker bar won't damage anything provided that you use the clutch tool, and not the gearbox/rear brake. All bets are off if you try to use a breaker bar on the M10x1.25 alternator shaft bolt cold if 648 has been used.

I've never used a thread locker on that shaft. The 50 Nm torque setting together with the Bellville washer has always been sufficient for the half dozen or more shafts I've replaced. I've checked them at 5,000 and again at 10,000 km and I've never found one loose. Haven't bothered checking beyond that.

My advise would be to go no stronger than Loctite 263 on that bolt, if you use anything at all, and don't use Benelli's reduced head M10 bolt. A standard R8.8 M10x1.25 bolt will be stronger.

PS. I use a calibrated Warren & Brown 323500 Torque Wrench. When I set it to 50 Nm, I know it is correct.
Thanks for that, I've looked at the workshop manuals and also laurences write up on the replacement z25, I asked the question to see what people had used and their success. My concern on the z25 bolt was that I could undo it by hand when I opened it up and don't really want it happening again, that was with the Belleville washer as well.
 

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Discussion Starter · #23 ·
OK friends,

Z25 bolt done, sheared in two but was still holding on the bearing sleeve!.

All cleaned, all rebuilt (without threadlock at the mo) new oil. For some reason neutral light isn't coming on, and when I attempted to start it sounded blooming awful as if somethings rubbing. Proper noisy grinding kinda sound. Killed it as quick as but now stumped, sprag clutch? Clutch not set properly? Any help great fully received!

Pierre
 

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Discussion Starter · #25 ·
Noise was on cranking and I think on running (to be honest it sounded wrong so I killed it!) the neutral light was working before I changed the z25 so I'm confused about that! Sounds like a clutch cover off job, I reckon I haven't done something right with the clutch! Can I crank it over without the clutch plates in place? Let's see what tomorrow brings! Thanks for the help 😊
 

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Discussion Starter · #27 ·
Looks like it a a gearbox out job now, something really isn't right! Am I correct in thinking is a remove sprocket and chain, remove water pump (drain?) , put into Forth gear, remove the bolts and it pulls out? Have I missed anything?

Pierre
 

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Discussion Starter · #30 ·
The more I think about it, the more I think I've done something wrong! Z25 looks like it's in properly, no lateral movement, meshes with the clutch housing cleanly. I can spin the z25 one way with no noises and the other way won't move so sprag clutch looks like it's engaging. Really baffled as it wasn't making that noise when running so I'm guessing it's mechanic error somewhere...

Pierre
 

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Discussion Starter · #31 ·
Oki doki, one problem solved and another encountered!

Z25 fine, happy days.

Stripped clutch and rebuilt making headway, however...

In neutral all spins freely, however in any gear its locked. Clutch lever works and operates basket but still locks out... Haven't fired up just in case the gearbox is toast.. Help!!!

Pierre
 

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Discussion Starter · #34 ·
Hi all!

Well, I have some progress, but still not sure all is good!

Stripped everything down again and rebuilt, no metal fragments in oil, nothing in sump, no nasty bits anywhere. Neutral light all good, alternator seems good and charging, gearbox fine, clutch looks fine, fires up, but seems to be making a whining noise, settles down after warming up but blipping the throttle makes it come back! I have a couple of videos of the sound but can't attach as it says they are too large! Can anyone help?

Thanks to the masses!
 
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