850 Mk2 & Mk2A Discussion Split From Another Thread

[jsnorton]

Your date should be well before Jun 73 - what does it say on the red and silver plate behind the headlight?

No, the numbers are really just serial numbers. It appears that there were some overlaps in the numbers.

The RH4 head (I'm pretty sure) tells you MK1 and the serial number is soundly in the MK1 timeframe.

If you order the factory from AN, you'll know a little more. How much I don't know. In 72 it was simply the serial, model, and color - not even combat or not. In 74 quite a bit more.

when i bought this bike from my cousin in 1978 he had taken the reg plate off when he repainted the frame and apparently lost it. I just recently put a new plate on from AN. I know it is a 1973 but just guessed at the month. Thanks, maybe I will get the records from AN just out of curiosity.

 

[marshg246]

Below is what I have so far. The only oddball is 3104xx Jan 74 - all the rest have serial and date in order. The certification labels say "Date of manufacture" but that is hard to understand - we know that the dates are well before the dates in the records AN has. Here are the ways the dates might make sense to me:

1. The frame was prepared including the certification label and "put on a shelf". When the engine was later installed it was stamped to match.
2. The engine was built and "put on a shelf" with a tag saying when it was built. The certification label was stamped once the engine was in the frame.

From the limited factory records I've seen, the certification label dates precede, usually by a lot, the dates in the records for 850s.

Using Feb 73 - Feb 74 (middle of the month) we get about 1010/month. Using all, we get about 1128/month. Using Feb 74 - Aug 74, we get about 1365/month. Since 750s were still being "built" in 1973 they would have been cutting into the 850 numbers in 73. So, I think the average was 1200-1300/month for 850s.

Would like more data points, especially info on the lowest and highest numbered pre-MKIII 850. More data points will increase the accuracy.

300376 Feb 73 ???
3017xx ??? RH4
307241 May 73 RH4
307542 Aug 73 RH10
3077xx Sep 73
3087xx Sep 73 RH10
308743 ??? RH10
309643 Oct 73 RH10
310311 Nov 73 RH10
3104xx Jan 74
3104xx Nov 73
310528 Nov 73 RH10
311032 Dec 73
311188 Dec 73 RH10
312xxx Feb 74
315114 May 74 RH10
31604x Jun 74 RH10
31661x Jun 74 RH10
320691 Aug 74

If people are willing to provide the info, I would be happy to compile it for the 750s and MKIIIs as well.

 

[maylar]

319532, Aug 74 on the tag. RH10 head and definitely a MK2 (upgraded swingarm). Original owner.

I think people would also be interested in know the associated Mark designation, based on the build level. Of course you'd have to know the bike's history and what might have changed since it left the factory.

 

[Gerald Jensen]

Below is what I have so far. The only oddball is 3104xx Jan 74 - all the rest have serial and date in order. The certification labels say "Date of manufacture" but that is hard to understand - we know that the dates are well before the dates in the records AN has. Here are the ways the dates might make sense to me:

1. The frame was prepared including the certification label and "put on a shelf". When the engine was later installed it was stamped to match.
2. The engine was built and "put on a shelf" with a tag saying when it was built. The certification label was stamped once the engine was in the frame.

From the limited factory records I've seen, the certification label dates precede, usually by a lot, the dates in the records for 850s.

Using Feb 73 - Feb 74 (middle of the month) we get about 1010/month. Using all, we get about 1128/month. Using Feb 74 - Aug 74, we get about 1365/month. Since 750s were still being "built" in 1973 they would have been cutting into the 850 numbers in 73. So, I think the average was 1200-1300/month for 850s.

Would like more data points, especially info on the lowest and highest numbered pre-MKIII 850. More data points will increase the accuracy.

300376 Feb 73 ???
3017xx ??? RH4
307241 May 73 RH4
307542 Aug 73 RH10
3077xx Sep 73
3087xx Sep 73 RH10
308743 ??? RH10
309643 Oct 73 RH10
310311 Nov 73 RH10
3104xx Jan 74
3104xx Nov 73
310528 Nov 73 RH10
311032 Dec 73
311188 Dec 73 RH10
312xxx Feb 74
315114 May 74 RH10
31604x Jun 74 RH10
31661x Jun 74 RH10
320691 Aug 74

If people are willing to provide the info, I would be happy to compile it for the 750s and MKIIIs as well.

307546, Aug 73, RH4

 

[marshg246]

319532, Aug 74 on the tag. RH10 head and definitely a MK2 (upgraded swingarm). Original owner.

I think people would also be interested in know the associated Mark designation, based on the build level. Of course you'd have to know the bike's history and what might have changed since it left the factory.

What I would like to do, but haven't because I don't think people would participate is to make a system where you enter this info plus several other things (airbox, frame backbone diameter, chainguard, etc.) I would it also to list known dead bikes. For instance, I used the basket case of 209458 to rebuild 201251 and I used the untitled bike 307542 to rebuild 320691. 209458 and 307542 will never be on the road again.

 

[MichaelB]

The 3077** Sep 73 listed has a RH10

 

[marshg246]

A few more have provided data:

Serial Label Date Head
201251 Dec 71 RH3
300376 Feb 73
3017xx ??? ?? RH4
303xxx May 73
307241 May 73 RH4
307542 Aug 73 RH10
307564 Aug 73 RH4
3077xx Sep 73 RH10
3087xx Sep 73 RH10
308743 ??? ?? RH10
309643 Oct 73 RH10
310311 Nov 73 RH10
3104xx Jan 74
3104xx Nov 73
310528 Nov 73 RH10
311032 Dec 73
311188 Dec 73 RH10
312xxx Feb 74
315114 May 74 RH10
31604x Jun 74 RH10
31661x Jun 74 RH10
319532 Aug 74 RH10
320691 Aug 74

Still, the only oddball is 3104xx Jan 74 I would really like to know more about this one!

 

[marshg246]

If yours is listed with missing info, please email me a marshg@gregmarsh.com. If you would like to add your bike(s) to the effort - email me. If you have a factory or NOC record, I would love to get the info from that as it verifies other info. I am keeping no record of the owner of the bikes published.

Some things are becoming even clearer that they were before. For instance, the way the factory kept records changed a few times. 1971 a simple ledger with quite a bit on info, 1972: A simple ledger with very little info, late 1974 more info on pre-printed forms, but still hand written on the form.

In 1972 and before, the certification label date appears to be close to the actual build date. In 73/74, the date on the certification label was sometimes months before the actual build date and sometimes out of order with other bikes. Also, MK2/MK2A were being built well before 1974 but so far I don't have a factory record for any early MK2/MK2A to corollate the date. Many of those records are missing from ANs collection.