| Author | Message | ||
     Benm2 |
I've been thinking about converting a blast motor over to diesel, as an experiment. Thoughts so far: 1. Already a long-stoke, slow turning motor 2. Not really concerned about hp 3. Easy to work on 4. Under-stressed crank (?? same parts as the twin with only one cylinder??) The thought process: 1. Get a small diesel fuel pump, and find a spot to mount it. Probably go electric to avoid weirdness with a PTO design on the engine. 2. Use mechanical injection, old-school diesel. Might be a trick to convince an electric pump to fire a mechanical injector though... 3. New piston. Need really high CR, like 22:1 4. Fabricate a spacer to replace the carb, and slap an air filter on the end. It SEEMS like it might be a fairly simple conversion, if not the prettiest project. I expect big clouds of diesel smoke on acceleration, and lots of noise. The cam timing might not be optimized, etc. Still though, seems like it might be fun. Comments? | ||
| Bombardier |
buy a single or twin cylinder diesel generator motor and bolt that in. | ||
| Hughlysses |
Search around on the net, some retired Harley engineers have already dieselized a big V-twin. You might be able to use some of their components. Not sure if Blast components would stand 22:1 CR or not. You can get by with less, especially if you use a turbo. Turbos should be mandatory for diesels- better power AND better economy. The Royal Enfields still made in India were available as diesels and used an engine such as Bombardier suggests. ~10-15 HP max though. | ||
| Jramsey |
Why make a slow running engine run even slower? What would top speed be? maybe 34 MPH tops. | ||
| Ft_bstrd |
600 miles per gallon. | ||
| Xl1200r |
I have visions of broken bits of cylinder wall and head blowing apart and through your leg. I'd find a small engine to just put in there. | ||
| Benm2 |
Diesel generator motors are huge, heavy and have no gearboxes. http://www.dieselbike.net/harleydavidson.htm The top bike has already been done, but turbo. I'd like to avoid turbo, KISS. I'm not sure, but I don't think that the PEAK combustion pressures are any higher with a diesel than they are with gasoline engine. The diesel KLR650 conversion bike being sold to the military gets 100mpg. I'd be into that! Getting back & forth to work would be about all it would be good for, but that's really all I want. | ||
| Sarodude |
So this would be a REALLY good time for a math and engineering insaniac COUGHblakeCOUGH to jump in here and explain what sorts of mean and peak combustion pressures we might see, the yield strength of whatever rod / pin materials, how little combustion pressure it would take to pull the head / jug studs out of the cases, and how easily we would fracture our puny little air cooled cylinder walls... If only SOMEONE would shed some light here... -Saro | ||
| Slaughter |
That KLR motor is a totally new design that uses almost NONE of the KLR motor parts except some tranny stuff. http://www.hdtusa.com/ Surf around their website - you will see NOTHING on that engine that looks like a KLR. There's almost nothing on the inside in common either. It's a purpose-built diesel that just uses the Marines existing inventory of KLR gas bikes. | ||
| Natexlh1000 |
I don't think any aspect of the blast engine would be able to withstand that kind of a pounding. Our bikes have just 10:1 compression ratio and have enough trouble keeping all those gaskets clamped together. I can't even imagine what 20:1 would do. | ||
| Pushrodpete |
"how little combustion pressure it would take to pull the head / jug studs out of the cases, and how easily we would fracture our puny little air cooled balls..." Fixed it for you.... | ||
| Corporatemonkey |
Isn't the military KLR motor designed to run on just about any combustible fuel? | ||
| Rfischer |
Does anybody recall GM's failed attempt in the 70's to convert the 350c.i. small-block to diesel? Unmitigated disaster. And they had resources waaay beyond any a BadWebber is likely able to muster. Give it up. | ||
| Newbuellertoo |
Yeah, but Badwebbers are way smarter and more inventive than a bunch of Dweeb G.M. engineers. p.s I'm an ex G.M. employee and I remember "The Great Diesel Disaster"  | ||
| Sarodude |
Fun times, Pete!  -Saro | ||
| Benm2 |
Steve, it was their website that gave me the idea. Their site says something to the effect of "consumer version on hold since the military contract is making us so much money" or something like that. About the GM thing: (1) I imagine that somewhere in the back of the room were the (quiet) dissenting engineers when those were brought to market, and were overruled by marketing. (2) I honestly wouldn't care how reliable it was, it would be a fun experiment. Reliable enough to run & require some tinkering would be fun, then I'd get bored with it, put it in the garage, start a spreadsheet of things I'd need to change to get it working right, then completely forget of its existence and move on to the next shiny object that distracted me. Its a disease... |
