1980 Rootbeer Bobber

[wannabridin]

So I have some measurement data from my cylinders and pistons. It seems like something wonky was done...

I measured with a 3-pint inner mic for the cylinders and a standard OD mic for the pistons. Measurements were made at the top, middle and bottom of the bore as well as the lowest point of the cylinder. Piston measurements were made 10mm from the bottom of the skirt (as the manual outlines) as well as halfway up the cylinder perpendicular to the pin.

It appears that I have 2 different sized pistons?? Bottom line, I believe I'm going to have to go with a 2nd over piston to make everything consistent. Thoughts??

Oh, and I double checked all the measurements, they are correct. My only guess is the 3 point mic might be averaging too much of the out of round.

 

[wannabridin]

i believe I'll go with these: http://www.ebay.com/itm/74-76-YAMAH...S-1-/131527195895?hash=item1e9fa1bcf7&vxp=mtr

hopefully I can still get the bore and hone for the $100 a local shop quoted me.

 

[TwoManyXS1Bs]

Good job with the measurements. Yep, left cylinder was bored 1st over to 75.25mm, right cylinder left stock at 75.00mm. Not terribly unusual, economy fix. Maybe something happened to that left side, like worse case holed piston. If so, double check everything on the left side (head, valves, crank/rod, ...etc.), in case something was missed.

Yer spot on with your 2nd over plan...

 

[wannabridin]

Awesome. Thanks for the advise. I'll double check everything I can and get back at it!

I know the head looks good, valves appeared to be straight and free in their guides, everything else seemed to be fine. Crank has been rebuilt and put back within stock and welded. I'll be sure to double check though.

 

[wannabridin]

Ordered a set of VM34's after Chris at Limey bikes convinced me to. Now trying to decide on which manifolds to get. I like the tapered ones that MMM/Heiden sells, and I've read they make quite a noticeable difference, even on a mostly stock bike. Thoughts???

I ordered the 2nd over pistons. Local machine shop will do the bore/hone and check balance for $80. they're also going to check all engine mating surfaces for flatness for free and address them if needed.

also sent off my xs1 regrind to Megacycle for a slotted cam sprocket install. I'm going to be running 0.026" copper head/base gaskets, so having the slotted sprocket will help with dialing it in.

Overall, I have most everything I need to put the motor back together. A little list of the work done to the motor:
-OD 5th
-Mild port job
-valves re-cut
-XS1 cam regrind w/ slotted sprocket
-2nd over pistons
-.026" Cu base and head gaskets
-elephant feet tappet adjusters
-PMA/pamco
-hyd clutch w/ single piece rod
-alto 8 plate clutch pack
-VM34's
-handmade exhaust
-Hughs oil cooler
-Heiden sump filter

can't wait to get working on everything!!

 

[figure8]

Check out the intakes Wes sells at Counter Balance Cycles, really nice.
http://counterbalancecycles.bigcartel.com/product/xs-650-intake-manifolds

 

[wannabridin]

those are nice. but if i'm going to spend that much, i'd rather just spring some extra for the tapered units the MMM or Heiden sell. I think there's more benefit from the tapered units.

also forgot to add: i'll be running a 520 chain setup to shed some weight. 18T front and 34T rear. That should lend a pretty good all around cruiser, ya?

 

[wannabridin]

Well, got my pistons, cylinder, head and upper case half dropped off at the machine shop. "At least 2 weeks" to bore the cylinders, check the valves and inspect the sealing surfaces for flatness. $80 isn't a bad deal and they do great work, so its not too bad.

Also got my slotted cam sprocket back from megacam. Nice quality and good people to work with.

 

[wannabridin]

Got a little mocking up done.

Also got my cylinders back from boring. Engine is almost ready to start reassembly.

 

[wannabridin]

Been ages, and the project hasn't moved much. I'm prepping the bike for a move to storage, as I need to get a car into the garage. I was mocking some parts up to get the bike to a roller and I've to admit, the stance is just perfect for what I wanted!!!

 

[wannabridin]

Also, can a moderator change the title of my thread to "1980 Root Beer Bobber" please?

Thank you!!

 

[helios79]

the stance is just perfect for what I wanted!!!

Absolutely agree with you, I am also going for the same with my '80,

 

[wannabridin]

The only thing that will be tough, is making sure the stance is just right when the bike is loaded down. I'm not quite as concerned with how perfect it is with me on there, but I certainly want it to be right when sitting. I figure my best bet to to align it as close as I can to parallel with the workbench, and then tweak the forks once it's finished. I've not even begun thinking about rake and trail. I just hope it has decent riding characteristics when it's all said and done!!!

 

[wannabridin]

Got the new bars mounted on so I can get it moved into storage. I had a set of stainless z bars made and they are absolutely perfect for fit and looks!! Just have to tighten up a few things and seat the tires and i'll be able to store it :-\

 

[wannabridin]

Realized I never threw these up here. Some pics w/ the shocks and new bars to show the stance..... someday..... (I've finished up more of the welds on the frame, just need to do the neck and coil mount)