| Author | Message | ||
     Jaimec |
How can an engine, with not just one... not just two, but THREE counter-balancers still have so much vibration?? This thing should be GLASS smooth! I've ridden quite a number of bikes with counter-balanced engines and none in my recollection vibrate as much as the helicon engine. Why is that?? | ||
| Pizzaboy |
It's a v twin? | ||
| Chevycummins |
Single crank pin V twin. | ||
| Blake |
Not. | ||
| Fresnobuell |
Vibes are there, but not enough to be an issue | ||
| Ccryder |
My level of vibration changes with: ambient temperature, engine temp, fuel load and how I have been riding. This may be a SWAG but....... the AFV are changing and this results in a change in perceived vibration levels. Some rides she is VERY smooth, some ride are lower frequency vibes. Just my $0.02 and YRMV and................ ;+} ( this is all soooo subjective that I'll have some more coffee and it will all probably change tomorrow LOL) | ||
| Fresnobuell |
Vibes are reduced with richer fuel mixture for sure, so Neil is right about his SWAG. | ||
| Pizzaboy |
Aw c'mon chevyvummims!! You know better than to say the rotax is a common crankpin like the sporty motors!!! Jeez ya rookie! | ||
| Blake |
BadWeB Hall of Shame nominee? | ||
| Xl1200r |
Gotta be up there,  I don't think the vibes are all that bad, but all I've ever had for street bikes has been the 1125, an XB, a rubber mounted Sporty and an Ironhead Sporty. I think it's just inherent in twins. Even my girlfriend's 250 Ninja gets some vibes. | ||
| Clarkjw |
If you add fuel and advance spark, vibes go away. | ||
| Luisemilio25r |
Excuse my ignorance but, what is a single crank pin? what is the other type(s)? thanks. | ||
| Jaimec |
It IS a single crank pin, but unlike the Sporty motor, the connecting rods are side-by-side, not "Knife and Fork." Since they are side-by-side you get a "Rocking Couple" imbalance. That's what the third counterbalancer is there for. The other two are to damp out the secondary imbalances from the two pistons which are mounted in a 72 degree V. If they were mounted at 90 degrees (a la Ducati) each piston would act as the other's counterbalancer; but then you'd end up with a much less compact engine than the Helicon. Everything is a compromise. The vibration is a low-frequency thrum, rather than the high-frequency buzz you get from an IL4. It's less annoying, but it's still surprising how much of it there is. At highway speed there is a lot more vibration than I ever had with my M2 Cyclone or XB12Ss, for example. Neither one of those engines were counterbalanced (and that was easy enough to see at idle). | ||
| Slaughter |
Single crank pin (common to BOTH connecting rods) - pics from my rebuild. First pic are the stock (right) and the 2008 - lightened and balanced (left) Second pic is looking down at the tongue/fork connecting rods on the common crank pin:   | ||
| Chevycummins |
Nice picture slaughter! I also believe that some of the vibration may be part of the spark timing map. I think a few people have altered their ignition maps and it would be interesting to see what they have found. | ||
| Ponti1 |
At the Thunder-And-Lightning event earlier this year, I rode the bike Teach had at Western Reserve which had the "performance flash" from the E-Bay offering applied to it. Absolutely smooth in every rev range, and the bike only had about 520 miles on it at the time. It actually felt sort of wrong to me since I am so used to the feel of my 1125. I think that product is only adding fuel, so I can't speak to the spark advance. | ||
| Clarkjw |
Ponti, the entire spark map is different on the performance flash. | ||
| Chevycummins |
Running the engine richer will slow down the combustion process thus similar to retarding the ignition timing. I'm getting some more dyno numbers this week and will experiment with it once I get all my data logging stuff. | ||
| Ponti1 |
Thanks for clearing that up, Clarkjw. I didn't know that. Either way, it was smoooooth. I guess that means fuel/spark is the ticket. | ||
| Teach |
The black 1125's are smoother...  | ||
| 1_mike |
Chevy, all - Yes...advancing the ignition timing does smooth out much of the vibration. Also as others have said...I added some fuel (just fuel) to mine last weekend...and the vibration is noticeably different. Ponti1, all - The "performance" maps allow the user to alter "both" the fuel and advance/retard maps to his/her hearts content. I'm still learning what my bike likes best on the road. Actually kinda fun trying different map values. Mike | ||
| Avc8130 |
What are you guys using to edit the fuel/spark maps? ac | ||
| 1_mike |
Avc - It's made by a guy in "Ohio", that has "Sport Bikes". Got the hint...? All strung together, they are three bad words here. Mike | ||
| Slypiranna |
Add bar end mirrors and/or bar end weights and forget about what the counter-balancers actually do for the engine. Proven well over a year ago to make you find something else to wonder about. You will be pleasantly surprised if you try and don't question the above prior to. It won't matter then. | ||
| R2s |
I don't think the vibration is bad at all for a liter plus V-twin. Very similar to my Ducati DS1000 mill. I like to feel the pulses. | ||
| Bigblock |
I don't know, compared to a 1098 my 1125 feels like a blender that lost a blade and then had some bolts chucked into it. Not necessarily in a bad way, but all the same... It ain't smooth, not compared to a 90 deg big inch V | ||
| Teach |
Welcome back Sly... Jim | ||
| Slypiranna |
 ... Hey Teach! Give this thread starter some advise on "tuning" to smooth his bone stocker! | ||
| Teach |
Jaimec.... My experience with my bike and a number of others who have had the same modification is to alter the mapping. It will smooth out the bike and you will get better performance. PM me for more details. Teach |
