Engine Blueprinting

[Mick Milakovic]

I'm getting ready to rebuild my '75 MC-5 motor and was wondering what "engine blueprinting" is?  How is it done and is it worth the time/effort?

Mick Milakovic
Delphi, IN
765-268-2570
[email protected]

[DKWRACER]

Ther is an article which explains porting for the 250 motors, authored by Carl Cranke, it is avail and if you need a copy, send a SASE to:
Tom Brosius
209 So Yates St
Denver, Col 80219
Should be done by a competant 2-stoke specialist, it may run as much as $250

 

[DKWRACER]

STOP and think!!! I find that there are many who think that "I feel the need for speed" is a total answer to their racing needs, I could argue that in the hands of a skilled rider who has surpassed many obstacles a faster motor might actually be the answer. I am reminded of a very old quote: " in order to finish first, first one must finish", KTM motors are well within the realm of reliability, proper maintenance and care are part of the process... Not one to boast, but I pay particular attention to maintenance of the entire process, why?, because I would like to finish, give the bike a good chance and you may reap the benefits of your efforts. These include but not limited to quality suspension, great tires, tuning the brakes, perhaps improving the rider goes a long way too..
Tom Brosius
#69R

 

[naga418]

I am not an expert but when one refers to "Blueprinting" a motor it is my understanding that they are going to completely disasemble the entire motor and put it back together making sure that each and every part including cases etc... match as closely to the original blueprint as possible. Engines come off the assembly line in many cases way off the original specs but they are within exceptable tolorences and therefor pass inspection and run fine for years to come. The German's as well as many other European countries have much tighter tolerences than we do here in the states and this is one reason they make such good stuff. There are other govenment standards in many parts of Europe that help in this as well such as steel quality, plastic quality, etc....

I sure hope I got this correct, like I said I am not an expert nor do I play on the internet:)

1973 Berkshire 100
First Penton, but won't be the last!

[Larry Perkins]

That is a very good explanation of blueprinting.  It is not porting to make different but matching to make it the exact way the engineer intended.

 

[john durrill]

Mick,
 in the Still Keeping Track issue # 15 summer of 2002 Kent Knudson did an article with the setup for a Ahrma 250 Penton running in the sportsman class. see if you cna get a copy from Doug or if your a POG member you should have it. covers almost every thing you should  need to know on the motor carb and pipe set up. The # 18 Fall issue covers frame mods.
 if you can not get a copy. we can scan it and post it in the Library.
John & Peter

 

[Mick Milakovic]

Thanks for all the replies!  I didn't want a "radical" motor, just one that ran as well as it possibly could.  I thought blueprinting was a matter of matching things, just wasn't sure if it was something I could do myself.  I'm getting ready to join POG, so I'll try to get issues 15 and 18.  Hopefully I can get back issues.  Thanks all!

Mick Milakovic
Delphi, IN
765-268-2570
[email protected]

[FMF MX]

Mick -
I had both my 125 husky and 125 penton "blueprinted" and muldly ported by a very knowledgable engine builder/friend. The most important thing is not to scrimp on crank bearings, seals, etc, and to make sure it is done by someone who knows how to set up and measure tolerances. Both of my bikes are very fast and reliable. The penton pulls espically hard, having been ported to carl cranke's specs from an old penton service bulletin that was based on the "Mettco" team port specs. I'm 220 lbs and can pull holeshots on this thing in the sportsman 125 intermediate class against elsinores, so I know its fast. Just make sure whoever you have do it knows how to build a sachs. I recommend Doug Wilford, since you live back east. Good luck.

Bart Carrigan

[imported_n/a]

Bart, maybe you could share the porting specs with the group or tell us where we can find them.  I think it would help us to build engines to beat those Elsinores more frequently.

Glenn

 

[FMF MX]

Glenn -
I'll be happy to send you a copy of the port specs. Anyone else who is interested can get them from you. Email your snail mail address to me @ [email protected] and I'll send you what I got. I can try to scan them in to email them, but don't quite know how. Got to get the kids to help me. The snail mail will be my backup.

Bart Carrigan