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(edit)..... one boot. lol.
The Shop
But for f**ks sake, go to 4.42 in the video to see the relationship of the countershaft center to the swingarm center - how high it is above the SA pivot. Then, if you've no idea of a standard CS to SA center relationship, go looking for pictures of how Honda have it with the original engine.
A millimeter or two can make a huge difference, especially with a powerful, torque heavy engine. You deviate from the original frame / engine relationship, and there has to be an 'architectural' reason for it, that you can't overcome, or, a good geometric reason for it - Not bloody fitting convenience. This looks to be at least 10/15mm above the original motors CS to SA setting.
That set up, is utterly, utterly dreadful. It's detrimental effect on the suspension and handling would be immense.
There'll be people that think it's acceptable, but not me, or anyone who knows about suspension and basic geometry and engineering. And, of course the builder and owner, will think it's 'perfect'.
It may look pretty, but it's a complete f**k up.
I've done dozens of Hybrids over more than 4 decades, and I strive to retain as close a replication of the Countershaft placing, in relation to the Swingarm pivot, as possible. I learned the hard way, way back in the early 70s, as a teenager doing my first conversion. It was only about 4mm off. (high) but it truly gave me problems.
That is a gorgeous bike. Though I bet the 250 motor would be a better fit and solve some issues that were raised above.
Definitely impossible to determine just by looking at pictures and coming to the conclusion that it must be shit because it isn’t the same relationship as the old 500 frame. May be a bad deal, or it could be a big improvement......
Pit Row
I'm not near my CRE500 at the moment, but dim memory puts that center to center of 67/ 68 / 69mm.
Modern bikes have gone smaller on that measurement, it just depends on the engines architecture. I think later CRFs are around the 65 / 63mm, but, once again, that's from memory. So, the difference isn't that great.
CS to Case / Swingarm mount is something you are stuck with, for the most part. It can be changed by a non concentric insert / non center lined) insert, or re-boring of a case away from the donor engines original center line, with a new insert. I've done that sort of thing a fair few times, even when it was a matter of gaining just a few mm.
Look to the engine relocation kits that Dubach and a few other companies had for YZFs, a few years back, and you'll see examples of what I refer to.
The main thing is the Height of the CS, in relation to the SA pivots height. Up higher than std, and you introduce more 'pull' on the swingarm upwards - lower, more pull down of the swingarm.
Look, a non concentric CS / SA set up has 'variable' chain torque influences, there's no way around it. It is, in effect, a bit of a ' Engineering Bodge'. But hey, a Concentric CS/SA pivot, that many Engineers will look at as a Holy Grail, has it's own weirdness, that most of us just can't / don't / won't come to grips with. Swings and Roundabouts, and, necessary compromises as they say.
Now, the later, and especially current CRF frames have a sloping down / pot belly engine cradle, so the height of the CS in relation to the SA pivot , when the cradle is on a flat, horizontal stand, does look outrageous. So, I daresay my first estimate of 10 / 15mm higher than the std Engine orientation is a bit much, but, I still think it's higher than the CRF engine is, and that can only be detrimental to the suspension and handling, with so much Torque ( while modern, std 450s now have , largely, more HP than a std, ancient 500, their torque is still much less, especially at low revs). I remember a few seasons ago, with the gen 6 ( may have that generation # wrong) CRF450 chassis, one of the big improvements was Honda dropping the CS center, in relation to the SA pivot, 5mm. Whenever I do a conversion, and I don't mean just 'AFs', I strive to get the CS to SA pivot center to center and, especially the height relationship, as close as possible to the OEM combo. And, in quite a few, when putting in a much more powerful / torquey engine ( say, with a CRF250X chassis in use), I'lI try for a slight lowering of the CS height.
For an example of something that may end up very badly, there's 'Too Fast Max's' / Lazer999s' (?) Mega 700cc 2T into a 'Berg engine conversion, that he's got a series of videos on. Now, if they leave the engine as it is positioned now, with the cut cradle and various grindings they did in the video, it's going to be horrendous. I do hope they are going to cut the cradle completely off, just forward / at the footpegs, and make a whole new cradle, to rotate the engine , and have the engine fitted well. A whole new steel, or alloy cradle, is not hard to make, but so many don't do it.
Because that’s what I want to do
The pictures are from slightly different angles but they are definitely very similar.
https://brcracing.ca/
https://www.facebook.com/andrea.ilrappa.rapaccioli/?ref=page_internal
In a good way, of course!
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