| Author | Message | ||
     Ohsoslow |
I have searched around a bit and haven't seen any threads with a issue similar to mine. On first start up for the day I usually let the bike idle until the cold message stops blinking and then go in my way, recently I have noticed a rattle from the left side of the engine in between 3k and 4k rpms. This happens at any speed with in the rpm range, clutch in or out, and stops after about 2 miles or so of ridding. I have speculations as to what it could be but I would like some feed back from you guys. | ||
| Metalrabbit |
hard to diagnose "rattle" noises on the 1125,, startup on a six cyl CAT motor is quieter. | ||
| Ohsoslow |
It's funny that you make that analogy, I just had a c-15 cat come in to my Job yesterday with a rattle it sounded just like an 1125 at an idle, it ended up being the air compressor. | ||
| Thefleshrocket |
My '91 CBR600F2 had an automatic, oil-pressure-fed cam chain tensioner from the factory. That thing was a piece of crap. (The CCT, not the bike.) The cam chain would make a rattly noise for a few minutes after startup.. cold startup, hot startup, whatever, it made the noise. The problem was that the CCT would take a while to build pressure and properly tighten the cam chain, and while it was building pressure, the cam chain would be noisy. I finally replaced it with a manual cam chain tensioner and that resolved the problem. I don't know what the 1125R engine uses for cam chain tensioning, but if it's oil-pressure-fed units like the CBR's motor has, it could very well be a failing CCT. I'd take it to the dealer and let them have a listen. | ||
| Jeepinbueller |
Mine sounds absolutely HORRIBLE for about 5 mins until the CT get up to around 175*F, then everything's peachy and stays peachy until the engine gets cold again. I'd really like the reassurance that everything's okay .. for sure ... from H-D. We'll see what they say when I get my clutch cover replaced. | ||
| Petethekiller |
It's piston slap..... The pistons have very short skirts therefore rock back and forth slapping the cylinders. When the engine reaches operating temperature the pistons grow in size to their proper tolerance fitting better in the cylinder and not slapping the cylinder walls. those of you who have built long stroke big bore motors with short piston skirts know the sound. Pete | ||
| Jeepinbueller |
Oh really? That's the first time I've heard that -- I'm obviously no engine builder. So it's due to the short skirts on the pistons causing the piston to slap ever so slightly until they thermally expand to tolerance? Makes sense to me, I hope that's what it is. It just sounds really loose and horrible for about 5 mins (even shorter on hot days) ... nothing I can't deal with. | ||
| Ohsoslow |
Pete, this is exactly what i was thinking, I don't know what the 1125 pistons look like so I wasn't 100% sure but it is what it sounds like to me, just wanted some other input | ||
| Metalrabbit |
Its all from the cold slack (so to speak) between the moving parts in the upper valve drive train mostly. I use to hop up aircooled and L/C VW motors for various uses. At first start-up I was usually on the creeper checking for oil leaks to appear while the engine is fast idling. The sound was like metal thrashing until the temp got up and damn near't all of it went away. And yes, you could hear the pistons goin' back an forth as well. | ||
| Thefleshrocket |
I don't think it's piston slap. If that was the case, the implication would be that this noise is normal for 1125s. The Rotax 1125 IS a noisy motor, but it's noisy regardless of coolant temp. Mine sounds the same when I fire it up as it does after I've been riding for a while. If there are any other 1125 owners nearby, see if you can stop by and listen to how their bike's engine sounds compared to yours. I bet you won't hear the same noise if yours is "horrible" when cold but then quiets down. | ||
| Dipstick |
What Flesh says. Mine sounds the same all the time also. 09R-8000mi. | ||
| Chevycummins |
Never noticed any piston slap noise on mine, just lots of gear rattle from all the balance shaft gears. You can try to listen to mine but its a little hard to hear the engine with the race exhaust on it. This exhaust fixed all the noises on my bike! | ||
| Petethekiller |
I know mine is noisy when cold...as soon as it reaches temp it quiets quite a bit. Look at a cut away photo of the 1125..it has very short piston skirts. I cannot listen to any of your engines and diagnose them correctly, but mine sure sounds like a normal short piston engine aside from all the other noises it makes. | ||
| Ohsoslow |
It has done it since day one from what I can remember 1800 miles on it now, the very first thing that came to my mind was piston slap just because of the conditions that it happens, I just wanted other opinons. Chevy i would like to listen to yours one time, the only thing is mine only does it on first start up after sitting for over 6 hours or the engine is completly cold | ||
| Chevycummins |
Stop by my work sometime and take a listen, I'm there from 7 to 3:30. | ||
| Spank |
These engine noise issues have finally gotten me paranoid. Do any of you have a ticking noise? The sound is much like when the valves on the Ninja I had years ago were out of adjustment. I only have like 4k on the bike...could it be valves already?? | ||
| Freight_dog |
Spank, I have 1900 miles and mine sounds like ticking to me also. It does seem to go away some when it warms up, but I was thinking valves as well. The Helicon valves are known to get tight before the first scheduled adjustment. I was already planning on checking mine well before they are due. | ||
| Jeepinbueller |
When I dropped Ginger off at Frederick I asked what their experience was with the Helicon. Their response that it's definitely a clanky engine at cold startup until reaching running temperature, and that it seems that when they are new they don't make that extra noise but seems to grow into it. I mentioned piston slap and the tech pretty much shot it down but didn't really extrapolate any further. Basically said it may not be right, but it's definitely normal from their experience working on them (and they have an extensive resume working on the 1125s and are an awesome dealership for us). (Message edited by jeepinbueller on May 26, 2010) | ||
| Dannybuell |
Chevycummins - "This exhaust fixed all the noises on my bike!" LOL. I am waiting for the exhaust slip-on shootout to do the same thing. THe E-B-R exhaust is a beautiful work of art. I too have noticed the cold start upper cylinder rattle that quiets down as it warms. My first introduction to this was a 69 Z/28 in 1971 when everyone said; "piston slap, the 302 was built loose for racing". If the Rotax was tight cold what would it do at 10,000 rpm, seize? |
