Top End Rattle

[GreenMachine]

How much is too much? I got my T500 finished on Christmas eve, registered yesterday. Put about 50 miles on her today, everything perfect except for a god-awful rattle from the barrels from idle to 2700rpm.

Once you get it to 2800 it sings like a bird. It's starting first kick, idles like a swiss watch but there's this damn rattle... My mates say "bah, two-stroke, they all do it, ride it like you stole it", but it sounds loud to me.

Motor is stock. Rebuilt the bottom end but the barrels were max oversize and seemed ok so I put them back together as they were. The noise isn't clutch related and seems to come from the top end. When you kill the motor, the last thing you hear is a final little death rattle.

In a related question - this is my first bike in nearly 10 years and my first two stroke ever - where in the rev range do you guys do most of your around town/40mph kinda riding? I did 50 miles today, most cruising between 2500 and 3000 - am I not revving her hard enough?

Thanks guys!!

NH

[titan performance]

Glad to hear you got it done Nick.....I don't think there are any hard and fast rules as to how hard you rev the bike, but they all need the cobwebs blowing away occasionally.
Difficult to comment on the rattle without hearing it though. Did you replace the small ends and gudgeon pins?
How are you getting on with those pipes?

[Craig380]

Like Titan said above, hard to tell without hearing the motor, but the 500 twins have BFPs (big f*cking pistons) and they do rattle some. Generally, if it's piston slap (relatively harmless), you'll hear it when the motor is under zero load (for example when blipping the throttle at idle. If it's the wrist pin bearings you'll most likely hear it prominently when you throttle off to change gear on the road (especially at higher rpm).

This is just my personal preference, but I reckon it's best to let strokers rev rather than lugging them at low rpm ... I'd suggest keeping the revs above 2,500 when you're on the open road. The 500s do have lots of torque which makes them easy to ride.

Your friends are right to some extent, strokers DO rattle and as Kawasaki triple owners will testify, can rattle even after a fresh rebuild. Get to know her and see how you go

[GreenMachine]

Thanks for all the advice, gents - realise it's hard to diagnose a noise over the inner-net, but if any of you want to pop down to sunny Brisbane, Australia there's a bed and a fridge full of beer here!

The pistons weren't in great nick when I had the motor apart - a couple of scuffs and detonation marks, but they were on second oversize, it was running before and I was out of money... Now that I'm loving the bike so much I'm keen to sort it - whipping the barrels off is no big deal.

Regarding revving, I'll start exploring more of the rev range as I get more used to it - I've currently struggling with trusting a bike I built myself (is that spindle done up?) and also being paranoid about all the lunatics in f*ing cages (got knocked off my honda in '01 and haven't ridden since)... But I had a smile on my face and I can't wait for the next ride...

Titan - the pipes and rearsets are great - might need to put a tactical dent in the lhs pipe, as I'm having trouble getting my cowboy boots under the lever for upshifts (although this may just have been me missing gears through incompetence...

[alanr]

I have the same model with a recon motor and rattle.I worry if its not rattling.mine starts first kick.if it doesnt it means I havent turned the key on.give it a blow out every now and then to clear the oil out and just enjoy.

[titan performance]

Nick.....so glad to hear you are enjoying the 500, and the Titan components you purchased.

These old strokers are mechanically noisy.....that being said, some are more noisy than others.
Back in the late 70's a few of us had 500s, and one of my pals bought a bike, (75 T500M), that I had spotted in someone's front yard. It hadn't moved for a year, so he knocked the door and ended up giving £90 GBP for it. It was stock...ish, but ratty. Chrome and paint were shabby, and it became affectionately known as the black bastard ! Out on the road the B/B was a match for any of the other bikes, but the noises that came from that motor were totally outrageous. We were all convinced that it's expirey was imminent.......but no ! It was thrashed mercilessly on a regular basis, and changed hands through our group of mates several times over 3 or 4 years. It never received the luxuries of maintainance or repair, and ended up with a mate that used it to commute to uni on a reguar basis.....about 200 miles each way !
The engine never "let go", or even broke down....it was totally reliable. The worst that happened was a silencer falling off late one night on the A6, and having to be retrieved the following day. Eventually, lumps fell off from around the motor, and it was left in Nottingham, in a hedge, which eventually grew around it.....that was back in the early 80s.
Ironically, my mate who left it there, received a letter from the DVLA a couple of years ago informing him that somebody had applied for a registration document for it..........so it lives again !

[Craig380]

I'll second what Titan said. A noisy motor does not necessarily mean it's about to expire.

A few years back, the top end of my 380 triple was quite rattly with piston slap. I knew it was worn, but the bike would still indicate 95 mph on the speedo in 5th gear any time I wanted, so it wasn't lacking performance.

I decided to overhaul the top end, and when I removed the head & original barrels, sure enough, they had pronounced wear lips on the thrust side. The piston rings also had gaps you could drive a bus through, in addition to having no 'spring' left in them at all.

I rebuilt the top end using the best parts from two good, lightly used sets of barrels and pistons. Piston / cylinder clearance bang on factory spec, new small ends, and new rings gapped just right. The motor was (and is still) lovely and quiet, even when cold .... but was hardly any quicker than the old, worn, rattly top end. It still puts 95 on the clock any time I want it to, just like before .... it just sound happier doing so now.

There's some sort of lesson in there somewhere

[CJF]

My GT500 had a pretty loud piston slap sound before I had the top end rebored with new pistons. My cylinder/piston clearance was still barely in spec, but i decided to rebore anyway because of the noise. The slap noise is no longer there now. You still here minimal normal noise for a 2 stroke, but nothing like what it was before the rebore.

[parksie]

Hey NH.. "Sunny Brisbane my A$$"

[GreenMachine]

It was sunny at the time!!! I'm now dodging thunderstorms and lightning strikes in Darwin... How is Canberra?

[parksie]

Damn sight dryer than Brisbane at the moment. Only problem with Canberra is you lot vote them in and we have to live with them
Darwin has nothing but Storms or at least it has every time I go there.

canberra weather wise Perfect at the moment, hope it holds out for the trip to Phillip Island at the end of the month.

Anyway.. back to the thread

[GreenMachine]

Back on the top end rattle... I think it may have spat whatever was rattling out the exhaust - didn't seem nearly so noisy on my last short ride... Although maybe I'm just getting better at ignoring it!

Will report back after more miles.

[tz375]

Let's hope it's all OK.

I hope you banana benders aren't planning on having another flood . The VIC government is still all bent out of shape about their funds being diverted up north and the Green Automotive fund was cut off to pay for flood repairs which was unfortunate.

How is the restoration/recovery coming along?

Have to admit I liked QLD when I drove up there years ago, but too far from all the good race tracks.

[titan performance]

Ooh !
I hope that was a joke about spitting something out of the exhaust.....

[GreenMachine]

Let's hope it's all OK.

I hope you banana benders aren't planning on having another flood . The VIC government is still all bent out of shape about their funds being diverted up north and the Green Automotive fund was cut off to pay for flood repairs which was unfortunate.

How is the restoration/recovery coming along?

Have to admit I liked QLD when I drove up there years ago, but too far from all the good race tracks.

Hope there isn't another flood - I've only just finished picking roof sheets out of gum trees on the farm! The recovery in Brisbane is almost complete - bar a couple of suburbs on the southside with a few unrepaired houses you'd hardly know it happened.

The bike, I hope, is similarly fine. Although I do worry when engine noises self-heal...