Building my own two-stroke "Mongrel" - Inspired by CharlieT & TedT



Well this day was a long time coming, but got my tires mounted, and wheels back on the bike. I'm working on a pre-flight check list and gotta order a few other odds and ends before I can take it for a puttering around initial test ride :)




Ride height wound up at 32in on the seat with the tires, no sag which is pretty good I think.



Rear swing arm angle at 15 degrees droop, again, no rider weight.




Front rake on the forks 27 degrees, without a rider. This is with the shortened rear shock, so if I put a regular length one back on it, that would steepen it up if I want something a bit more faster turning feeling. Don't know until I ride it, but I wanted to be on the longer rake bit more stable end of the spectrum to start with, at least.









While it looks tall, its mostly just ground clearance under the frame and engine be cause the frame is made some compactly. The plus side to that is, should be plenty of room between it and the ground to run an underslung exhaust like I wanted to, eventually :)
 
Popeye SXM said:
Great to see some progress. That exhaust is mad, I love it

Thanks! I am looking forward to building version 2.0 - and trying to go under frame...should be fun. I wont be able to resist not taking it for a rip with this one on it atleast a few times first though... :)
 
Yesterday I was able to finish the shifting linkage. A little hokey looking at the moment but with some clean up I think it will be okay. It does cycle through and work, and since each rod end is adjustable + can move it on the shaft splines I have a lot of adjustment in positioning. The one thing is I had to extend a lever down from the shaft pretty far to connect the ball end, to clear under the footpeg. In turn, this makes the shifter throw long to fully engage a gear. It kind of has to be this length to clear under the peg bracket. So, you guys may wind up getting your way and having at least the left side welded to the frame or I have to get a bit more creative in how it hooks up.

I will get it off the table and sit on it some soon and see if its a totally unreasonable amount of throw or just a pain in the ass. At the moment it seems tolerable. I'm getting pretty close to being able to take it for a ride around the yard at least.

Also gonna put the SV shock back on that I had originally, now that I have some tires, and see how the stance changes also for shits and giggles.
 
Re: Building my own two-stroke "Mongrel" - Inspired by CharlieT & TedT

Looking forward to seeing it roll & smoke!


Sent from my iPhone using Tapatalk
 
Re: Building my own two-stroke "Mongrel" - Inspired by CharlieT & TedT

BillyGoat4130 said:
20170723_135323-XL.jpg
[/url]


Getting closer to a run and test ride!!

That spannie stick out like a hernia!
It's awesome!

Don't burn ya leg :)


Sent from my iPhone using Tapatalk
 
Okay ya'll, these CR Hi-bend dirtbike bars are not going to cut it, even rotated forward like that. May wind up trying just a piece of 7/8 chromoly in a drag bars configuration, but any other suggestions/ideas?

Also, I wound up with that Hayabusa front master cylinder, and in my ignorance didn't realize that the reservoir was made at an angle to accommodate the clipons that turn down...if anyone wants to trade for something else that would work better, let me know?
 
RR100 said:
Love it. Spectacularly balanced and muscular looking.

Thank you very much! Kinda had an idea in my head of the shape and stance this thing would take on eventually - got pretty darn close to it! Still quite a few things to button up but luckily I'm not that far away from it.
 
Looks insane - in a good way.

What size master cylinder do you need? I may have one in a suitable size ( and what size is that one?)

Straight bars are all wrong for your wrists. Try a set of drag bars or so called superbike bars - slight rise and correct wrist angle.
 
Thanks for all the kind words and comments folks, I definitely appreciate it! Like I alluded to in the beginning, I'm the type of guy that builds stuff with what I have available for the most part. So my machines may not have quite as much polish and spit finish as others, but they'll be built with a bit of everything recycled or incorporated into it and that's my style. I look at some of the builds I see guys finish and my mind races wondering how the hell they got everything so clean, spotless, and perfect, and how will they ever keep it that way hahaha. Having a vision of an idea, and then cutting and welding stuff together isn't that hard. You just gotta be willing to try, fail, and retry until it works, failure isn't an option.

I was *completely* out of my league when I started building that hybrid engine originally. I didn't even ever really expect it to run. I started with junk yard engine cases (scrap aluminum bin, seriously) and a cylinder that had the skirt broke out of it, because the idea intrigued me but I wasn't about to try to start welding and milling on a set of good 250r cases ($$$). I eyeballed so much stuff. I remember the first time I had the cylinder bolted onto the cases with a crank in it, and it would barely turn through because I had the base gasket surface so out of square the piston was dragging on one side of the cylinder so bad it'd barely turn though. But, I did some thinking, some doing (always the most important part!), and I got it corrected. Somewhere a long the line I reached a point where I was like "Shit, I think I can actually make this work"...and I had friends, good friends, tell me it was a waste of time and would never run, or why would I not just go buy an aftermarket big bore cylinder and stroker crank kit for $2k and be done with it, but that's just not me. I like to take the long way around things. Its not just the end result that's important, the journey is too. And so that's been the story with this bike, beginning with buying a junk rotax cylinder in 2010. Kicking the stuff around for a few years and actually starting on the engine building phase later in 2013, finishing the engine in '15, and then starting the 2 wheeler phase in tail end of '16....I like to think of it as a little bit of my own "Munro Special" to a degree. No present plans to use old sewer pipe for cylinder liner, though.


Irk, I built mounts onto the sub frame for that seat (had to modify the mounts some). I'm not crazy about it, I wish it was a little bit longer as there isn't any room to scoot backwards really, but it was cheap, and it'll work. It currently bolts down with 6x 6mm bolts. I've been thinking lately most of my electrical including a small battery will have to go under it, so I may need to make a quick change or pin system to latch and release it. Probably some sort of aluminum trough to lay in the sub frame and then the seat goes over to house things. I intend to run it for the time being, but certainly subject to change.

teazer, bars are 7/8. I've now got double line banjo bolts in both 1.0 and 1.25 thread to fit whichever the master is. I never even knew banjo bolt mounts in 1.0 were a thing until this. I suspect a set of bars will be one of my next purchases. Another friend suggested "Clubman" style bars, and they look like they have a little bit of rise, as I'm trying to maintain a bit of rider up type position. The vibration and power curve will make it difficult enough to ride comfortably so I want to avoid clip ons or anything that is super low like that...
 
BillyGoat4130 said:
Irk, I built mounts onto the sub frame for that seat (had to modify the mounts some). I'm not crazy about it, I wish it was a little bit longer as there isn't any room to scoot backwards really, but it was cheap, and it'll work. It currently bolts down with 6x 6mm bolts. I've been thinking lately most of my electrical including a small battery will have to go under it, so I may need to make a quick change or pin system to latch and release it. Probably some sort of aluminum trough to lay in the sub frame and then the seat goes over to house things. I intend to run it for the time being, but certainly subject to change.

Food for thought:

I use GSXR pillion seat mounts. They run them on Ninjas and others too. You can find them on eBay for $10 - $15 all day. This is one I mounted on my BMW, but I use them on all of my bikes. Good secure fit and a remote cable to unlatch.

5adcc8b8d7447628629e16ebb18712f7.jpg


7eff5d17761573dc8f0ea010b0eaa79b.jpg
 
I'm the type of guy that builds stuff with what I have available for the most part.
Its not just the end result that's important, the journey is too

Good for you. That is why I am enjoying your build so much. I used to make a living repairing fixed farm equipment, which meant in the middle of harvest, I had to get everything working again as fast as poss with what ever I could find (never pretty )
My current project (build post coming soon) is more about the build than the finished bike. Pls keep the your pics coming
 
irk miller said:
Food for thought:

I use GSXR pillion seat mounts. They run them on Ninjas and others too. You can find them on eBay for $10 - $15 all day. This is one I mounted on my BMW, but I use them on all of my bikes. Good secure fit and a remote cable to unlatch.

<snip on the pics>

That is quite a brilliant idea. Something like that for a gas tank mount would be really nice also when you have to peel it off a dozen times a day to jet a carburetor also...

Boy now you got some gears a' grindin!
 
Back
Top Bottom