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BWWAAAAAHAHAH! Huuuuh that is really one cool looking bike...but he sure will get dirty, driving it!

This reminds me of a guy over here in germany, that suddenly sat on 24 Chainsaws he did not know what to do with.
Because those chainsaws had a top notch motor and he had lots of time on his hands, he slowly but surely developed a plan
for a motorbike driven by those 24 chainsaw motors!

This is the result

THE DOLMETTE



Some guys are just plain crazy!
And he even did some races with that thingy....unfortunately he lost by a hair against a 400 PS Audi.

The engine

What makes the Dolmette unique in engineering terms is its 24-cylinder 2-stroke power plant. Nothing quite like it has been seen before. The combined power of 24 DOLMAR chainsaw engines is fed into to a 5-speed Harley-Davidson transmission by a series of twelve toothed belts.

The engine in question is the one used in the PS-7900 professional chainsaw, which currently boasts the best power-to-weight ratio of any professional petrol chainsaw in the world â€" just 1 kg per PS. In standard trim each of these high-performance air-cooled 79 cc units generates 4.6 kW of power (6.3 PS) at 9500 rpm. A specific output of 59 kW per litre is outstanding for a chainsaw, and the secret lies in DOLMAR’s High Performance Combustion (HPC) technology. This term refers to the special design of the six gas exchange ports in combination with the asymmetrical combustion chamber head and the crankcase configuration: the result is a highly efficient combustion cycle with low exhaust emissions.

For use in the Dolmette the engines were tuned and tweaked to deliver 5.2 kW of power (7.1 PS) at 10,000 rpm. Maximum torque delivery is 5.5 Nm at 7,750 rpm. When all 24 are combined, the result is a 24-cylinder power plant with a total displacement of 1.9 litres, a power output of 125 kW (170 PS) and 130 Nm of torque at the centrifugal clutches.



The combined power plant

The heart of the combined power plant is the central drive belt casing of aluminium construction. As well as encasing the eleven belts used to couple up the individual engines, it also houses the exhaust ducts for the cooling air. Twelve engines are mounted in two rows of six on either side of the drive belt casing. Each engine is held in place by means of two threaded studs that normally serve to secure the guide bar to the chainsaw power head. The individual motors are coupled together in sets of three by means of a double-sided drive belt, making up eight modules in all. The individual engines are not rigidly connected; instead they deliver their torque through the centrifugal clutch that is a standard feature of every chainsaw.

Through a sequence of three more toothed belts the power of the eight modules is transferred to a single output shaft, which in turn drives the clutch for the 5-speed transmission via a twelfth belt. The toothed belt drive also serves to gear down the speed of the high-revving chainsaw engines in the ratio 3.45 : 1, producing a manageable maximum of 4,500 rpm at the transmission unit. The friction loss that is inevitable with belt drives is less than 10%, which means that the maximum torque available at the transmission input shaft to power the bike is a massive 400 Nm

As a consequence of the non-rigid coupling of the individual engines via their centrifugal clutches, the combined power plant has a self-determining â€" i.e. totally random â€" firing sequence. In this case, because of the way a 2-stroke engine works, there are 24 ignition points during each engine revolution, or roughly one every 15º. In other words, this power plant fires four times more often per revolution than a 12-cylinder 4-stroke engine!

 

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I'm (almost) speechless..how he built it is fascinating, but WHY would you want to? Looks like something created for a 'Wizard of Oz' movie.
 I know someone who does the most unbelievable cabinetry..(woodworkers all scratching their heads wondering how he created the shapes and problem solved other areas)..but the finished product is something like a beautiful kitchen bench on an 2 plane angle and with cupboard doors that open in ways you would only imagine in a nightmare ????  ......still AMAZING THOUGH!
......like Midget Porn..hideous...but you can't stop watching!
 

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I like it. It's more art than motorcycle though.

PS I can stop watching Midget porn..... every time my Wife walks in :joke:

Sledzep
 
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Discussion Starter · #10 ·
That bike is way different than anything else I have seen... I personally would not own it, but it does portray the innovative depth and creativeness of the builder... :bigthumbsup:
 

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not for me!
 
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Discussion Starter · #13 ·
Spankster said:
WOW that is really diffrent... I think I saw it in Charlie and the chocolate factory... Him too... :eek:
OH...HELL NO!!! LMFAO!!! Thanks!! Needed a good laugh today!!!

Looks like if Tim Burton would make a bike...it would look like this!!! LOL!!
 
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