Lean can cause seizures? Yes it can. Been there, have the T-shirt. More likely with a 2 smoke, but in a case like this where they are WFO for ages, indeed it can.
...and based on today's Splitlath Facebook update, apparently Mark blew another engine in practice this morning. I wonder if they have any engines left?
^ Yea, as they've said several times, they went all the practice sessions and races last year on the same engines without a single failure. It must be pretty disheartening. This may be EBR's last chance for a decent showing in any motorcycle race.
Today's update from Mark. They're gonna try one more time...
quote:
Isle of Man TT 2015 update 10 -- One lap, Superstock practice, Monday:
Hi family and friends, if interested we got out for one lap of practice tonight but before half way into the lap the third engine in a row seized before even starting the mountain road. Coming into Sulby Bridge after clocking 170mph on the Sulby Straight, I down shifted into the tight 1st gear corner only to have the RPMs drop unexpectedly (again) with the rear wheel stepping out unexpectedly and almost throwing me into the same tree that Jenny Timmoth did a few years ago.
Something's wrong.
Got it safely to a stop, parked the bike against a hedge, again, and got a ride back The Grandstands on the back of another fan's bike, this time a group of cool dudes from Holland. I swear, I've never seen more of this beautiful island in the past 10 years than I have on the back of these fan's bikes this year. They navigate the traffic while I sight see like a tourist, looking out to sea, the hidden houses on the coast, the sheep, the birds, the clouds, the sun, the meadows and little pubs. No foot pegs for the back seat this time, however, for a 45 minute ride. Heh heh
I've helped to coordinate the final plan of action for the Splitlath team now which includes our tired but motivated team members Tony and Peter Ward among others installing our FINAL spare engine, only this time with one new variable (which I cannot discuss). Huge thanks to Ryan Farquhar for his good advice about racing big twin cylinder engines around the roads. Three motors in, three motors broken for this fortnight. Thank God they're only USD$11,000 each. <cough.> Poor John Dimbylow, the team owner.
Bottom line is we'll start our race tomorrow with yet again a new motor and an unproven overall scheme. Hopefully with any luck we'll finish it for once without incident.
In practice today before we broke I had to negotiate my bike through several crashes on the track. William Dunlop was laying in the middle of the road exiting a blind corner while his brother, Michael, who had rested his bike against the hedge next to the incident, kneeled down beside him.
William is said to be smashed up a bit, broken ribs and punctured something or other internally, but nothing life threatening. His TT is over. Hope he heals up soon. Guy Martin has taken over William's duties on the "Victory" Brammo TTZero entry.
Well done Bruce Anstey for his Superbike win last night and Hutchy for his Supersport win today. Good stuff lads.
Off to bed now, it'll either work tomorrow for us or it won't. I'll be covering the clutch lever with a bit more vigilance in the interim, that's for sure.
^ You may be right. I'd guess that some critical piece of information was lost between last year and this year, maybe due to crew changes? Hopefully they have nailed the problem and fixed it.
Mark said in his Facebook post they weren't even able to break this engine in before the race as the dynamometer in the pits was broken. Crazy.
Davegess, still odd to have identical failures in close succession. It would seem a common cause has to be found somewhere. Discovered a firm material fatigue life/limit did they?
Ace117, over revving to a seizure? Thought over revving was what is normally claimed for a valve float, valve strike/holed piston?
Thought over revving was what is normally claimed for a valve float, valve strike/holed piston?
And this cannot lead to engine seizure? Looks like to me those boys are riding the EBR like a IL4. Didn't the EBR WSBKs have similar problems when banging downshifts. YOu can't tell be there wasn't some serious over-revving going on slowing from 170 to a 1st gear corner.
Cory West told me that is why Dustin Domingiz blew so many engines in 2013 when they were both on the same team riding EBR's. He said you have to be careful with your downshifts because the rev limiter is useless in that situation.
If I recall correctly the 1190s rev limiter prevents over revving during normal engine operation however, downshifting into a lower gear at high RPM will cause the engine to over rev possible causing valve float and piston to valve contact. I cant recall the rider or race venue, but i remember reading about EBRs seizing Engines due to this. I could be wrong Im no expert just an observant gear head. Im sure some one on this board will recall what i am talking about, either way 3 engines seizing the same way at the same position on the track is a little fishy and NO Bueno.
If I recall correctly the 1190s rev limiter prevents over revving during normal engine operation however, downshifting into a lower gear at high RPM will cause the engine to over rev possible causing valve float and piston to valve contact.
All the rev limiter can do is cut the ignition off to prevent you from "powering" the engine past redline. If you drop down 2 or 3 gears at high speed, the momentum of the bike driving the rear wheel driving the engine will over-rev the hell out of it; the rev limiter can't do anything. The slipper clutch could help prevent this.
Mark rode the EBR without problems at IOM last year so it seems unlikely he would have forgotten how to ride it without killing the engine. Maybe someone on the crew was setting up the slipper clutch improperly?
Maybe someone on the crew was setting up the slipper clutch improperly?
Maybe the first time or the second time...but do you think they would miss this SO many times. This combined with the WSBK failures points points to something else that's failing. Of course IMHO.
Fresnobuell, given the rev limiter and slipper clutch it just seems very difficult to put it into the conditions for catastrophe. Repeatedly doing so certainly raises an eyebrow. Maybe more electronic buffers are needed in the shifting so one too many downshifts are an impossible condition to reach? Like a throttle by wire, a shift by wire with the computer between you and the transmission for just such an extreme condition.
I'm very disappointed in velocity. As far as I know the only American there and certainly the only American superbike and they dont even get a mention? Wtf! Most Americans wont even know who Hutchins is. Lol. Anyway, I'm glad Mark is doing some excellent coverage. Hope he does well in the senior. Best of luck!
They know what caused all their seized engines and they corrected it before the last race. He's not at liberty to say what the problem was due to a "sponsorship conflict". I'm guessing something like the wrong motor oil? Man, that's crazy. What a wasted opportunity due to apparently an easy-to-correct error.
I like the fact that he points out that there are no other Vs twins or 4s willing to get out there and try.
Unfortunately even though EBR may not have been the root cause, they will get the black eye and poor reputation for the failures. (No that they are not without failures, but I prefer they get nailed for the break downs they earned)
