hjennings
XS400 Addict
Maybe I'm looking at this wrong.
Like I said, I do not have access to all the data for bikes like I do cars. But for the sake of explaining my thought, I'll make up a bike.
So the bore of the XS400 jugs is A (jugs, not the sleeves). You look though the data and find that a Honda ABC123 bike has a jug bore that is 0.100" larger than the XS. The Honda ABC123 piston and sleeve internal bore is a corresponding 0.100" larger. Pistons and rings for the Honda ABC123 are readily available.
So you bore out the XS jug by 0.100", press in the Honda ABC123 sleeve, and use the Honda rings and pistons.
The only issue you have to look out for then is piston height and wrist pin size. Hopefully you can find a piston with the same wrist pin to piston top height and you can simply use the ABC123 piston fitted to the XS rod. With the numerous similar sized bikes out there, I'm sure a suitable piston could be found.
I you cannot find a suitable piston to use on the XS rod, then you'd have to play around with piston/rod combos (which then causes you to take rod bearing size into account... which isn't too big of a deal... if it is smaller than the XS just turn down the XS crank). This could cause a lot more machine work and expense. But if you were able to find a piston with matching height then the only machine work would be to overbore the jugs and press in the new sleeve.
Agreed, you are not going to get much performance boost from that, but being that finding new XS400 rings and pistons is harder than finding hens teeth, this is a viable option to rebuilding one of these engines and keeping it on the road.
This sort of stuff is done all the time with automobiles. So am I missing something here, or can this also be done on these bikes (and many others)? Something I'm overlooking?
Like I said, I do not have access to all the data for bikes like I do cars. But for the sake of explaining my thought, I'll make up a bike.
So the bore of the XS400 jugs is A (jugs, not the sleeves). You look though the data and find that a Honda ABC123 bike has a jug bore that is 0.100" larger than the XS. The Honda ABC123 piston and sleeve internal bore is a corresponding 0.100" larger. Pistons and rings for the Honda ABC123 are readily available.
So you bore out the XS jug by 0.100", press in the Honda ABC123 sleeve, and use the Honda rings and pistons.
The only issue you have to look out for then is piston height and wrist pin size. Hopefully you can find a piston with the same wrist pin to piston top height and you can simply use the ABC123 piston fitted to the XS rod. With the numerous similar sized bikes out there, I'm sure a suitable piston could be found.
I you cannot find a suitable piston to use on the XS rod, then you'd have to play around with piston/rod combos (which then causes you to take rod bearing size into account... which isn't too big of a deal... if it is smaller than the XS just turn down the XS crank). This could cause a lot more machine work and expense. But if you were able to find a piston with matching height then the only machine work would be to overbore the jugs and press in the new sleeve.
Agreed, you are not going to get much performance boost from that, but being that finding new XS400 rings and pistons is harder than finding hens teeth, this is a viable option to rebuilding one of these engines and keeping it on the road.
This sort of stuff is done all the time with automobiles. So am I missing something here, or can this also be done on these bikes (and many others)? Something I'm overlooking?
I know others have tried looking for alternatives to stock parts but never posted any real or cheap results. If you can find a good plug and play it will be an epic achievement
