Honda-SOHC

Due to my existing cylinder bores being oversize and also being unable to obtain any 0.75 or 1.0mm oversize pistons to suit I'm on the lookout for a set of used barrels.  I really don't want to go down the expensive re-lining or big bore route, I'd like to keep the bike as standard as I can if possible.

Finish is unimportant but if possible I would like all the fins to be intact and the bores to be either worn standard or 0.25 to enable me to get a .05 re-bore if I have to. I've have tried e-bay and all the usual breakers but there's nothing available.
If anyone has a set let me know and we can negotiate a price.

Hope someone out there has something suitable to get one of these bikes back on the road 

Dave

Following an eventful afternoon in the man cave standing over the parts washer today (having to use the last of my annual leave and I've decided on a self catering holiday in the garage....)..... I decided to strip the oil pump for a clean and inspection.
First thing of note was the amount of 'O' rings present  . Having previously ordered all the required 'o' rings as shown in the parts book I was a bit surprised to discover there are three additional 'o' rings present within the oil pump itself that are not shown in the parts manual, Oh dear ! I toyed with re-using them but like everything on this engine somebody has been inside it before me and they have done what I was planning on doing,turning them around! I cant do that as they are not 'o' in shape any more but very flat where they have been squeezed down, several times it appears.
Does anyone know what size 'O' rings I should order and where I can get them? The parts manual does not list them so I'm a bit stuck, I'm sure my local Honda emporium will not stock them unless I can provide a part number. I can measure the diameter but not the thickness as they really are flat! The 'O' rings I am after are for the gearbox rotor (photo attached) and the main chamber oil seal (the one with the rotor shaft in the photo). Being an oil pump were pressure is everything I don't want to re-fit the old ones and potentially suffering a leak and loss of pressure. I have the other seals all brand new and ready to fit.
On inspection of the pump I checked for wear on the main rotor housing body, it appears to be scored (see photo) although I couldn't detect any discernible 'ridges' in the body with my finger nail although the housing is so small it is difficult to get a finger in there to test it!  Has anyone stripped a pump down before and is this type of wear common and is it acceptable? If not is there any way a repair can be undertaken as new pumps are slightly scarce at the moment!
Finally, I mentioned at the beginning of this post that somebody has already been inside this engine, this is confirmend as the main pump rotors (inner and outer) are punch marked and the punch marks should both be on the top face, they weren't the inner rotor punch mark was face down.  Looking at the attached photo, is the wear on the rotors acceptable?
Any advice would be welcome as always and despite the setbacks, shocks and horrors I'm actually enjoying the rebuild .
Regards
Dave

Hi All,
Its my first day here and I need some advice from the knowledgeable people who know and inhabit this forum.
Its a question about crankshaft bearings, big end bearings, bearing codes and general engine bearings.
Before joining the forum for 'real' today I have looked through a good number of posts regarding crank bearings but unable to find an answer I need.
I have bought a 400/4 in many, many boxes, you know, the 90% complete project with the vital missing 10% made of unobtainium materials.
I have completed stripping the half stripped engine and need advice about crank bearings.  Knowing from experience what a minefield measuring cranks is I used plastigauge to measure the clearances.  The stamping on the rear crankcase half are: BBBBA.  One of the crank webs has a number of 50106 although I am not sure if these actually mean anything.  I reassembled the crankcase with the crank installed and plastigauge placed on each bearing journal. I assembled the crankshaft in the bearings dry, no oil added to the bearing shells. I torque set the lower crankcase bolts to the required tension.  On disassembling I measured the plastigauge on the crank journals.  The readings were 0.050, 0.045, 0.063, 0.055, 0.050 (metric measurements).
Question 1: Can anyone please tell me if the bearings are within wear limits, I cannot find any reference in the Haynes or Clymer manuals advising what the wear limits of the shell bearings are?  I have a nasty feeling they are terminally worn. This leads to:
Question 2: How do I measure the crank journals accurately? I have a mic but this only reads down to 100th of a mm, Honda measurements are in microns (32+0 -0.010u)! Having measured the crank journals using the mic I have obtained the following readings: 31.76, 31.70, 31.82, 31.80, 32.00. Unfortunately I cannot believe any of the readings I have obtained as I get a slightly different reading every time I measure each journal, I'm talking of differences of 100ths of a mm but its enough to cast serious doubt.
If I do need new bearings I think I need Black, Black, Black, Black, Yellow?
Question 3: If I need black bearing shells does anyone know of a supplier, DS and CMSL don't have any. Should I start crying yet?
Question 4: Big ends -  Any advice please on a type of socket to use to remove the big end nuts, the nut is obscured by the curvature of the big end, a 3/4 socket is too big and a 1/4 socket wont move the nut. It doesn't hep that someone has already been there previously and rounded a couple of the bearing nuts, not badly but Mr Honda obviously didn't put them in like that!
Question 5: The con rods are marked with what appears to be a number and a letter, I though they should only have a number.  The numbers (and letters) I have found on each con rod are: 1D, 2D, 21(should it be an 'I'), 21 (same as rod no.3). The rods and ends are correct pairs, I can see they haven't been swapped with each other as the numbers and letters are stamped half on the main rod and half on the lower shell cap.  Can anyone advise what bearing shell colours I need?
Question 6: Can the con rod bolts be reused once undone or are they stretch bolts? (exxxpppeeennnsssiiiveee  )
Question 7: Does anyone know the OD and ID of the main engine bearings, the parts manual only provides part numbers, can anyone recommend a bearing supplier? Do I, or should I, replace the main engine bearings considering I have the engine in bits and never heard it running?

Apologies for all the questions, its just the crankshaft bearing issues appears to be a can of worms!

One last question, can anyone recommend a good painter, I have a tank with a slight dent in primer and a couple of new sidepanels from DS that also require painting in the F2 maroon with the pinstripes.

Thanks for reading this far  .

Dave