| Author | Message | ||
     Willmrx |
Just got back from a 10 day trip to visit the family for Thanks Giving. Went to go for a ride today after the bike had sat for 15 days and when I went to start it, it back fired and stalled out, attempted a second restart and when it started, it sounds like someone had put rocks in the cylinders! The bike was running great before, never better! It sounds like a rod bearing has failed. It runs for 15 seconds or so and dies. It has 50,000 miles on it 30,000 of them ridden hard. Has anyone had this happen to them before? | ||
| Coastrambler |
Only thought I have is check the injector plate. See if the backfire blew it out of the rubber sleeves that connect it to the cylinders. Mine did that a couple of times. It'll start OK then run really poorly as the plate rattles around. | ||
| Willmrx |
Checked all of the simple stuff, loose rotor nut, cam followers, shims, all look good. It's looking like a total tear down. Well, at least it's the beginning of winter, I hope to have it running by spring. | ||
| 651lance |
Sprag clutch? | ||
| Willmrx |
Yes I checked the sprag clutch, I had replaced it last Oct. I was hoping it was the rotor nut, but it was okay. BTW I just ordered your gasket set for the rebuild! I most likely will be buying more from you! | ||
| Willmrx |
Okay! Found that the rear cylinder intake valve had made contact with the piston. do not know why? Again, last ride all was well! Bike did not run any better. | ||
| Deanh8 |
This has happened to me on a stock 1125R, sat for awhile cold morning bent the rear intake valves after a mis start | ||
| Dannybuell |
what do the timing chain tensioners look like? | ||
| Willmrx |
Piston got kissed by the intake valves.   | ||
| Willmrx |
It is looking like when the bike backfired at start up, it cause the timing chain to jump a tooth. | ||
| Stevel |
I would suspect that the timing chains are worn out and are too long, allowing the chain to slip a tooth. After the valve collision, I suspect the valve stems will be bent. They too will require replacement. As far as available performance upgrades are concerned, no aftermarket parts are available for this engine. Dan Crower does sell cams, but they were not designed for this motor. I cannot say whether they are good or bad because I have no experience with them. I have been told that the profiles are from KTM. This came from Dan Crower. I have also heard of engine failures using them, but this is third hand info, but you should be very cautious and check everything before using them. What I can say is that any cam profile change is difficult because of available space. The head design makes valve float almost a certain disaster because when it occurs the valve shim will likely leave the spring retainer pocket and jam up the works. So, any profile that increases the valve acceleration will require stronger valve springs and none are available. I have written here on BWB quite a bit about this subject in the past, so I won't repeat myself again. Lastly, be aware that the big bore kit uses 106mm bores that are very thin and I believe are unstable. Several engine failures have occurred after their installation, so again be cautious and do your own research, before pulling the trigger. | ||
| 651lance |
If you smoked your cylinders I have three new pairs of them I'm willing to sell for $800 (for the PAIR) shipped to the lower 48. These are new in the box Buell cylinders that retail for $740~ each. | ||
| Willmrx |
My theory is, the bike has 50,000 hard miles on it and the timing chain, guides are worn. The fact that the bike sat for 15 days, caused most of the oil to drain into the oil pan, including the cam chain adjuster. When it backfired on the first start up attempt, there was not enough oil pressure to properly hold enough tension on the cam chain which caused it to slip a tooth. Just my theory and I am sticking to it. And thanks for all your guys input! For the cylinders they still have the honing makes on them, which was surprising to me. The other question I have is, where is a good place to send the heads to be rebuilt and have the ports cleaned up? And lastly I have decided not to get the big bore kit( Thanks Stevel for your imput!) and just get velocity stacks and have the head done and the ports cleaned up. | ||
| Willmrx |
Just a idea, instead of the having the ECM waiting three revolutions to start the bike, make it at least 5,to give the oil pump time to generator some more oil pressure. If That would increase the oil pressure. | ||
| Nuts4mc |
a) got a parts manual? b) I've had good luck getting parts from new castle hd in pa. c) it's a European (designed) engine I would look for a shop specializing in those brands: kinda like these guys: http://www.aspowersports.com/ ...with all those miles might be wiser to buy a used motor on ebay (a few listed under $2k) hth | ||
| Mesozoic |
I like the idea of increasing the number of revolutions to start the engine - definitely will help with oil pressure at startup. |
