Big end bearings lucky to catch this one

[Ryno]

Originally Posted by JarkkoT

+1

it's more dramatic to hit rev limiter with twin, because the piston +rod weights alot. four cylinder has much lighter pistons and rods. .

Not only that but piston speed is a lot higher as well

[JarkkoT]

Originally Posted by brent_b

I have seen mention of soft and hard rev limiters, do we have a hard type? I thought the whole reason for the rev limiter is to stop damage to the engine, not create it

yes, it's kinda last resort, engine management has to do something to limit the revs if the driver doesn't.

usually four cylinder bikes have such safety marginals, that you can hit the limiter all day. Like when I had 954rr, I used to just accelerate at first untill I hit the limiter, then i knew I was at the speed limit or little over. It's fun.

With speed triple 1050 the limiter is kinda low(9500), so I pretty much hit it daily.

daily limiter banging is not recomended for TL, 10k is not the same to all engine configurations.

[brent_b]

You live and learn i guess.. There is always a bright side, if you blow up a tls engine, you can throw a tlr engine in, its like Christmas!

[zippytlsr]

If it were me Pad... I think i would send the crank off for balance and polish, I just put NEW shells of the same size in when i put my motor together. I measured mine and all was within tolerances. Just my own guess here, but it does appear that a lack of oil has been an issue or maybe something got pumped through the system and made it to the bearing surface. Now i will be checking my oil with a damn microscope.

[Sam]

Originally Posted by pad

The Original shells are Brown
Should I stick with the brown ones or use the Yellow shells

Mic up the big end journal in 9 places (0 / 120 / 240 Deg on each side and also the centre) then average them out, check the rod codes (1 or 2) and then select the shell from the manual.

When you fit the new shells it's best to check with plastiguage as there are manufacturing tolerances on new shells

[The Ring-In]

Most erosion on shells is caused in some way by cavitation. that is when the oil has gaps in it. the gaps can be air or just blank space.

running low on oil , clearances too wide, excessive side clearance. too tight clearances at higher rpm ( go figure!!! . no actually the oil has to get out, if it can't you get problems. high performance shells are thinner at the join line to let oil out.)
high rpm may starve the oil pump from poor oil return. and of course high rpm high demand on oil, so the need for better oils.
aging oil pumps may get waeker too.

have a good hunt around before closing up the cases.

chek the rods for concentricity too.

The big ends rely on the the mains for oil pressure too so check these. ( if oil gets out here it starves the b/e

hope this helps

[zippytlsr]

damn.... you guys are freakn me out... i did plastigauge.. rackn frakn sakn crap!! yeah, it may work... but damn.... what a pain in the ASS. Practically got me ready to tear the motor apart just to make sure nothing bad is happening.

[Sam]

It doesn't take long to check when the engine is stripped

[cyclecamper]

Surprising sometimes how springy a stock rod is, and how much they can deform without breaking. I'm kind of hoping my Carillos will not just resist simple fracture, but cap might also hold shape and thus hold bearing tolerances better. Here's hoping! Since mine are the Yosh-spec Carillos, they have no oil-spray slot on their sides at all, instead they are EDM drilled their entire length to provide forced-oil lube to the wrist pins. But if I get even a spec of dirt into a big-end bearing, it will have no easy way out.

[JarkkoT]

TLR oil pump is better for cavitation prevention, it has feed for both sides of the pump. TLS has only feed from single side.

Oil cavitys form easily if there is gas in the oil. when pump sucks oil the pressure is going down and if there is any gas in it, it can easily turn into vapor under heat and low pressure. and we all know TLS is notarious for gas in the oil.