I remember these lightweight steeds that had an almost cult following in the UK, resulting in a large number of tuning parts becoming available at reasonable prices.
The noise of a gaggle of them pulling away from the lights all at once could and did break the windows of nearby houses.
The compression pressure of an exhaust tuned 2-stroke engine is necessarily quite low - because the cylinder capacity and the compression ratio "grows" at the rpm the reflected exhaust pressure wave effectively blocks the exhaust port and the engine power suddenly increases. Yamaha engines of that time were notoriously "sudden"...
I don't know the exact compression pressure but I would be happy if I did a test and achieved around 100 psi. My Suzuki of a similar design produced 105 psi on the kick starter. Much more pressure than that and there would be a danger of the fuel detonating in the cylinder when the engine "was on the port", usually resulting in a hole melted in a piston.
SOURCE: Question about motorcycle
Hi christina
They did build a XJ550 (in line 4, not V) in the early eighties, But that's the only road bike 550 that yamaha made. Check it out here.
Hope that helps solve your puzzle :)
regards
robotek
SOURCE: 1854-Yamaha V-Twin Motorcycle Engine
The horsepower of that mighty beast is exactly 100 horsepower (73.6 kW). Here's some of the other specs:
SOURCE: Have twin exhaust for Yamaha
Hi Martin 649
I think it is a Yamaha two stroke125, are you looking to sell it.
Martyn
SOURCE: i have a yamaha 100cc
Quote your frame number to your local Yamaha dealer they will have the search data you need
102 views
Usually answered in minutes!
×