Is it a FRAME UP

[rigwit]

Well, you all know from my first pics of stripping the bike there was a bit of the, "Hole" demon in mudguard/seat bracket well steamed off the frame and cut the infill panel  started to clean pipework welds for migging in panel and lo and behold what did i see.well the left suspension mount/gusset is completely gone  got frame back home n decided to investigate with the old dremmel.  the insides of the main frame tubes has completely been eaten away so need to be replaced. works  mig is uselass  .my semi pro home jobby is better,but have lost regulator n pipework in move. now as I'm very cynical on a job i would give out  to do and not see what was done because of the new gusset....I'm seriously thinking on buying a portapack outfit and setting up a yearly account with BOC  and doing it myself. then I'd know the job was done correctly  and properly  also there would be lots of panels and brackets new gussets  etc  to attach to frame - so would be used a lot. then I'm thinking if Ive got a gas torch why not make the swingarm myself with the machining done by my friendly firm, ( a bit more about them later) so then I'm thinking  get a level stand, i mean a true level stand  be like looking at an oblong table  with box section around it and angle welded inside  a true piece of marine ply put in with the centre cut out oblong so a 400-4 sump would go in but the main crankcases would be supported, buy some T54 tubing and make a new frame for it like the old ducati ladder frame.. this would involve  new tank made etc etc  but I'm toying with it only thing i haven't got  is the facilities i used to have  as Ive made frames at work for others but thats going back to late 70,s early 80,s   no pipe bender no lath no milling machine no facing machine  so all that would have to be done -out of -house so to speak  or get some boiler plate and make side jigs and heat form tubesmyself...  well thats the bad news  about my friendly machine shop. took some parts in to be machined up and some brass or sintered bronze top hat bushes turned up, and heat pressed in to worn clutch shaft operating cup  then reamed out once heat pressed in and an alloy  kickstart plug made and threaded into clutch cover caseing.  also picked up a 99% full motor to use as a mock up while all my cases go for checking/peening/blasted/primed then satin blacked,  so decisions decisions i need a fatter wallet  methinks  

[matthewmosse]

Sounds like quite a job you have to sort that frame, I know of a company local(ish) to me who build really nice frames for classic bikes, I know they do cb500 ones and even cb250 ones, pretty sure they even had a honda 250cc 4 cylinder? thing a year or so back. I belive their customers race their bikes so if you decide to opt for a one off frame without the hassle of building one, might be of interest. On my 500, I had to re make a portion of the rear frame and repair a few bits, wouldn't by itself be cost effective as boc accounts so expensive but it's also useful on the farm

[rigwit]

Sounds like quite a job you have to sort that frame, I know of a company local(ish) to me who build really nice frames for classic bikes, I know they do cb500 ones and even cb250 ones, pretty sure they even had a honda 250cc 4 cylinder? thing a year or so back. I belive their customers race their bikes so if you decide to opt for a one off frame without the hassle of building one, might be of interest. On my 500, I had to re make a portion of the rear frame and repair a few bits, wouldn't by itself be cost effective as boc accounts so expensive but it's also useful on the farm

  would it be jwmotorcycles..?

[matthewmosse]

you already know them then?

[rigwit]

Seen there site from a search bit aways from not so sunny yorkshire. so  dumbhead  here forgot about, Sponden in derbys  lot nearer  so gonna give em a ring and see what can be done............

[rigwit]

OK.
took tank to a local firm who specialise in top notch paintwork also do frame repairs......... went through what i was after, as a finished starter,  IE monoshock top trunnion mounting plate, rear foot peg hoops taken off, back top tubes cut just after mudguard/seat brace. no probs     .....so frame tank were going that afternoon to blaster (Monday) as didn't want to do any mods or lay out money if frame is past it so waiting for word back how it is, also went to my local engineering firm to see how they were progressing with the work i took, i did mention there were, "no hurries" on the work  but to find out theyhave not done anything so far was a bummer  so threw a bit of money at them to see if that speeds things up    on a downer  main journals n big ends are yellow D  standard  which are not available so Ive a choice can get  green and brown bearings both of which will give a 10 and 20 undersize respectfully, other way is to take it to hindle re-man and see if they can re-metal the original shells back to tippy top------no scores on journals or  housings  and no major wear on bearings  just a few bright patches.........but id like to keep the major parts as standard as poss with out going oversize

[Bryanj]

I think you are reading the shell sizes wrong as there are no such thing as undersize shells and your decimal point is in the wrong place, all colours of shell will run on a standard size pin just the oil clearance varies. I have many times built with all black shells and if run in carefully instead of just bedded in no problems arrise

[rigwit]

I think you are reading the shell sizes wrong as there are no such thing as undersize shells and your decimal point is in the wrong place, all colours of shell will run on a standard size pin just the oil clearance varies. I have many times built with all black shells and if run in carefully instead of just bedded in no problems arrise

D yellow is for a +0.008to -0 crankcase allowance, with a journal of +0 to -0.010 giving a running clearance of 20 to 46 u, Green is for a +0.080 to -0 crankcase allowance with a journal size of -0.010 to -0.020, and a running clearance of 22 to 48 u, Brown is for a c/case clearance of +0.008 to -0 and journal allowance of -0.020 to -0.030 and a running clearance of 24 to 50 u so my strip down was  D (yellow) which gives me a c/case allowance of +0.008 to -0 and a starting journal tollerance of +0 to -0.010 to run brown or green the journals depending on how round they are and are not tapered, would need a lick of either 10 or 20 thousandths of an inch to give me anything between 22 to 50 u clearance, or as said ,i could get the shells re-metaled at hindle re-man depending on cost of either green or brown with a journal lick over cost..










d

[Bryanj]

PLEASE check the numbers again its casing hole tolerance 0.0009 inch NOT EVEN ONE THOU in which there are 3 steps and same tolerance on PIN with 2 steps which means there are 4 grades of shell to cover a less than 2 thou tolerance gap.

Either your manual is printed wrong or you are looking at metric instead of imperial numbers

[rigwit]

PLEASE check the numbers again its casing hole tolerance 0.0009 inch NOT EVEN ONE THOU in which there are 3 steps and same tolerance on PIN with 2 steps which means there are 4 grades of shell to cover a less than 2 thou tolerance gap.

Either your manual is printed wrong or you are looking at metric instead of imperial numbers

It could be as half of it is in imperial and 1/2 in si units, crank is marked in 3 steps  ie : 1, 2, 3, which to me would mean 1 standard tollerance of original turning, and 2 oversize ( bearings that is) as si units were introduced during the last 18 months of my college training but i still work in imperial and yes ive worked down to u, 5 microns to be presice and on hand turned parts, also used to cast bearings  well the firm i worked for at the time did but we did it  but im buggered if i still have my rifller knifes/files ..........ah that takes me back ds are now showing  D (yellow) big ends but still only green or brown mains will mike up crank and check min/max of housing and work it out from there. 

[Bryanj]

Actually the crank pins only have two steps, its the cases and rods that have 3
Main journal case max 1.4182 min 1.4173; pin max 1.2992 min 1.2983 so thats a total variation of 0.0009 on the case and pin sizes, count the 0's after the point its not even 1 thousandth.

variation:- big hole small pin is 0.1199
               small hole big pin is 0.1181

so MAXIMUM TOTAL is 0.0018 or 1.8 THOUSANDTHS in which Honda supply 4 different shell sizes

Mind blowing the machining and measuring acuracy of the japanese isnt it

[rigwit]

"Actually the crank pins only have two steps, its the cases and rods that have 3"

400 has 3 for journal and 3 for case.   550 only have 2 for journal and 3 for case  .....