Honda CB750 Sandcast

Replacement and Reproduction Parts - The Golden Rules

kp · 3 · 1509

kp

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If you are a collector or restorer then chances are 100% you've needed to purchase a replacement or reproduction part at some time. I seperate the 2 as a replacement part (replacement being other than a factory replacement) doesn't necessarily resemble the part being replaced but is more about replacing a damaged or worn part to keep the item serviceable. Items from gasket kits to exhausts would fall into this grouping. In many cases it is irrelevant if the part exactly matches the original as it's more about serviceability and such may never be seen in any case. A replacement bearing, brake fitting or camshaft is not going to be seen so to most it is immaterial if it doesn't exactly match the original.
In relation to reproduction then that simple word says it all. The term is often loosely used as the reproduction part has only passing resemblance to original. Most however do reproduce their parts to match or closely the original item and attempt to also match performance specifications. The biggest considerations on reproducing a part comes down to three main considerations being capacity to reproduce, market call and cost. Other factors are also at play but in reality if it was made by man originally then it can be reproduced. It really all comes down to a single factor and that is cost. I know a little about this area as I have reproduced two specific items over the years for the sandcast these being the early brake hoses, and more recently, the early master cylinder cap. In relation to the brake hoses a major hurdle was to comply with the DOT requirements i.e. the part had to comply with current automotive safety standards. The point is that replacement and reproduction parts have to comply with current standards which may be significantly different to earlier standards. Asbestos in brake and clutch products is an obvious example
The reason I've started the thread is to basically get some discussion and interest occurring on the topic of reproduction parts. I agree the topic is not going to change the world or indeed change anyones set view about the topic but I thought it may be an area we might all have some interest in and would like to express that interest to the group as a whole. There is no right or wrong answer or view although some just don't hold with the concept of reproduction anything
I'll start the conversation by stating my view on the subject of a reproduction item.
I support the concept of reproduction parts if there is no alternative part available. My biggest gripe is around quality and matching original. To me if a company is going to produce a reproduction part then it must be exact exact exact just like the original. No half way and no cutting corners. If the word reproduction is used then it has to meet that criteria. If it doesn't then it should be labeled as a replacement. I personally would rather rebuild/restore an original part than use a reproduction. I'll give a single example (I could give a dozen though) Some of the #8 bolts being sold as reproduction  ???. The only similarity with these bolts is the use of the numeral 8 and the thread pitch The similarities end there as the 8 bears no resemblance to original. Yuk
Let's hear your thoughts  ;D
Yabba Dabba KP


Steve Swan

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i would ditto your remarks.

i would add, it's a hard and sometimes difficult life in the world of a restorer.  if one wants to be a purist, then even a restored original part is not longer a truly original part, assuming, of course one lives and dies by the axiom, "Original only once."

i compromised on 232.  debate back in the day, as i recall, could not decide if date codes were used on the very earliest of side covers.  i am not sure we still know.  so, i have Yamiya side covers on 232 and a Yamiya air box.  on purpose i left the metal seat pan original, so it's not got perfect black paint, but i did not want to endure listening to someone tell me i had fitted a repro seat, therefore i left the pain with it's original paint.  where ever i could, i used original parts.  imho, decisions for what entails a restoration are a very individual and personal process.  none the less, we do try to exact some idea to conform to our idea of original. 

i will say, based on my experience, antique motorcycle guys ARE HARDCORE when it comes to original.  as a whole, most antique m/c guys will take an "original paint" over an exacting restoration 24/7/365.  and i am referring to bikes that are at least 65 years old, and usually, 75, 85 and over 100 years old.  just as a reference point for bits of what drives my decision making process, some of you know i am restoring a 1927 H-D JD.  88 years old.  first off, try finding nos, very good or even fair condition original parts.  most chassis parts are ragged at best.  bringing a really ragged part back to original is a masterpiece of effort, but no matter how good the artist, inescapable and telltale signs of repair exist.  one will have 100's of hours and thousands of dollars in restoration expense, even when one does as much of the work as one's self is capable of.  and is a heavily repaired/restored part TRULY still original... ?  in the case of my 27, i literally started with an engine (broken crank cases) frame (bent) front/rear wheel hubs, transmission and a set of really nicely repaired/restored tanks which were no longer EXACTLY in appearance to original.  every motorcycle deserves a chance to live again, even if it's a lowly garage queen.  the way i look at it with my 27, i truly started out with very few parts, not even enough to look like a motorcycle and major parts were broken.  so, i made the decision to purchase numerous gorgeous reproduction parts, instead of spending 100's and probably even 1000's of hours restoring very rough condition original parts.  my 27 will never have the value of an original paint.  it will never have the value of a restored original machine.  but i can tell you, only with close up intense examination, will only the most experienced eye know i have "cheated" by using reproduction parts.  and i have taken a few parts and pieces that were once upon a time a motorcycle and will be a motorcycle again (that i can hardly wait to take a first ride on!)  at the end of the day, it boils down to what the bike means to me and no one else.   i have always been in old bikes for the passion.  i highly respect those who are EXACT to EVERY last detail.  probably my work is not to that standard.  none the less, i turn out some very fine work.

anyway KP.... thanks for a great subject and inspiring a novella from me !

ps - couple pics of my Dad with his 27... sleeping at edge of road on a 1000+ mile trip and in his ROTC uniform.  my apologies in advance for non-sandcast material !


Steve Swan

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don't know if i ever posted "before" pics of 232, but here is a couple of what i started out with...  had a K4 engine w/ fulcrum style carbs fitted.  broken unstamped cases came in a box.  original cases from assembly line long gone.  considering 232 went through at least 2 engine changes, i am still AMAZED to think 232 has so many of the hard to find parts on it, such as round o.f. cover, smooth oil lines, early brass vented carbs and round bead wheel came in boxes.  except for LR's, the only other items it was missing was thin lip alternator cover, 19 L tank and 11 hole seat.

still looking for thin lip alt.cover.... ! :o

sorry for the hijack, KP !