T: Fuel Tank Gas/petrol tank underside recess position (not the UFM recess) and shape

bmetcalf

Well Known and Active Forum User
VOC Member
I only needed 90 deg items for the cables I made over the winter, but these are 135 deg:

https://www.amazon.com/Shimano-Line...id=1522918284&sr=8-7&keywords=shimano+noodles

Cable solder pot:

Cable Solder.jpg
 
G

Graham Smith

Guest
This is an interesting thread. I have an early Series 'C' bike and was surprised to see that it had, what we call, a Series 'B' fuel tank.

Upon speaking with our knowledgeable Machine Registrar (@vin998 ), it would appear that us all discussing tanks (and RFMs) as Series 'B' this, and Series 'C' that, is wrong.

It seems that quite a few early Series 'C' machines had the 'early style' type fuel tank with the small cut-out and also, the 'early style' RFM.

I wonder what other components this refers to?
 

Simon Dinsdale

VOC Machine Registrar
VOC Member
VOC Forum Moderator
You are correct Graham. There is no such thing as a series B fuel tank the way most owners describe them. The large cutaway came in sometime towards the end of 1950. Its safe to say no series B machine was fitted with the larger cut out, but any series C made in 1949 and most of 1950 would have probably been fitted with a small cut out tank.

A lot of modifications / improvements in 1949 & 1950 had nothing to do with the different series.

Here is another. The early gear lever mounted off the footrest hanger and with the external linkage was used well into 1950. Again it was used on early series C's and so strictly speaking its not a series B gear lever. Your Rapide in question would have had such a gear lever. Aparently there is an advert that Paul Richardson as service manager placed in one of the motorcycling magazines around early 1951 announcing the new & improved one piece gear lever and other improvements. I have never seen this advert so cannot confirm the date.

I have previously explained the RFM changes. Again nothing to do with series B or series C. There was an 18 month overlap in 1949 & 1950 where the factory was making both series B & C side by side. During that 18 months a lot of slight design changes were introduced on both the B & C series at the same time. The factory was always short of money so they were not going to produce two different fuel tanks or RFM's at the same time.

Simon
 

davidd

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VOC Member
You are correct Graham. There is no such thing as a series B fuel tank the way most owners describe them. The large cutaway came in sometime towards the end of 1950. Its safe to say no series B machine was fitted with the larger cut out, but any series C made in 1949 and most of 1950 would have probably been fitted with a small cut out tank.

I have always thought that the small cutaway tank was not a Series change, although I think it came closer than you suggest. It may have been that the Factory instituted the change in late 1949 as a priority on the Flashes and Lightnings. I don't know about the Lightnings, but I have not seen a small cutaway tank on a Grey Flash. It is always difficult to know if the tank has been swapped out in later years, but there was little contemporaneous talk about carb clearance issues. The three North American Flashes seem to have survived well and all had large cutaways. All were built in early January of 1950. It is just as likely that some small cutaways were used on the other models until the stock was depleted.

The same applies to the shift lever. Many of these parts were used for the Flash/Lightning remote shift linkage, so the supply of the parts would have gone on through August of 1950 when the Flash was withdrawn as a model and they would have been provided as Series D parts on the Lightning.

Even what we call the Series C UFM was a Series D part as it was the only UFM supplied on Series D Lightnings.

David
 

Albervin

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VOC Member
I have always thought that the small cutaway tank was not a Series change, although I think it came closer than you suggest. It may have been that the Factory instituted the change in late 1949 as a priority on the Flashes and Lightnings. I don't know about the Lightnings, but I have not seen a small cutaway tank on a Grey Flash. It is always difficult to know if the tank has been swapped out in later years, but there was little contemporaneous talk about carb clearance issues. The three North American Flashes seem to have survived well and all had large cutaways. All were built in early January of 1950. It is just as likely that some small cutaways were used on the other models until the stock was depleted.

The same applies to the shift lever. Many of these parts were used for the Flash/Lightning remote shift linkage, so the supply of the parts would have gone on through August of 1950 when the Flash was withdrawn as a model and they would have been provided as Series D parts on the Lightning.

Even what we call the Series C UFM was a Series D part as it was the only UFM supplied on Series D Lightnings.

David
The Series C RFM is what you mean ? Yes?
 

Simon Dinsdale

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VOC Member
VOC Forum Moderator
When looking at all these changes in production like the tank cutaway I think you can ignore the special machines like Flashes and Lightnings as those were not made on in the std production area and so were probably altered for the specific bike. The large cutaway on a Flash tank may have been the inspiration to alter the standard tanks but that may have taken a while to filter through.
Were the tanks made externally? If so the factory probably altered a std small cutaway tank for the Grey Flash.
 

greg brillus

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VOC Member
The cut-away on the earlier "B" tanks is way too small anyway, I wouldn't mind betting they got plenty of complaints from owners with bent/pinched cables that something should be done to give a bit more room.
 

davidd

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VOC Member
The Series C RFM is what you mean ? Yes?

I should have included both. In an effort to retain rigidity, the D lightnings continued using the standard C chassis parts.

Regarding special parts, I think the Flash received more than the Lightning. If you consider all the special part numbers for the Flash, almost all the parts are custom, mostly because they were painted grey (as a result they received many part numbers.) But, there were more special parts that like the fork blades, UFM and RFM that had milling or drilling.

The Lightning chassis is difficult to identify without the numbers because it is mostly "off the shelf" parts.

I believe the tanks were outsourced. I would note that although the sample is small the Flash tanks I have looked at carefully seem indistinguishable from the production tanks. This would except the TT tanks, which were also outsourced and were truly custom. I think I got this info from John Bland, but I did not ask about the implementation of the large cutaway.

I think the original small cutaway was done to establish a better fuel capacity seeing as there would be more than a few prospective buyers that would note the small range. I suspect the Factory got a lot of feed back once there were many bikes in service.

David
 
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