kghowell1765

Hi Everyone
My first post. Glad to be here.
I just purchased a used Raleigh road bike. From the equipment, I'd say its roughly 1990 and in great condition.
The Rims area Araya and marked with "27 1W". Therefore, 27" rather than 700c.
I replaced the existing tiress with Vittorias that are 27 1-1/8". The issue is that the rear tire is now rubbung on the underside of the brake caliper. It seems that the wider width has increased overall diameter as well.
Am I correct in assuming that any 27 x 1 tire should solve this issue as it shoud be a smaller overall diameter due to the decreased cross section?

Thanks,
Ken

wheelreason

Generally, yes, wider tires on the same rim will have a slightly larger diameter. You may also be able to raise the caliper a tad depending on how much clearance you need. Or you can get an even wider tire and ride it until it pops, I read somewhere that works...

ps: It's also possible that is a 700c frame and someone switched the wheels to 27 and made it work with bubble gum and duct tape.

HTupolev

Yeah, a smaller tire should help, if things are right on the edge.

If you have the ability to move the brake pads down by 4mm, you could also potentially swap the wheels out for a 700c set to give yourself more room. But of course that would be a much larger investment.

kghowell1765

Thanks, really ppreciate your advice.

Maelochs

1990, most people were selling 700c by then .... measure the dropouts and see. If the rear spacing is 130 mm, then it was almost certainly a 700c bike someone put bigger wheels on.

There are a few Raleigh catlogs here (https://www.retrobike.co.uk/gallery2...gh/Catalogues/ (Whoops, sorry .. those are just pictures, not pdfs---Useless)) and somewhere else ... I have an '84 Raleigh (27" wheels, 126-mm dropouts, cold-set to 130) and I forget where I got the catalog *Sheldon Brown) but I was able to identify the exact model by the paint and the picture. (https://www.sheldonbrown.com/retroraleighs/dating.html)

Between the serial number info there and the catalogs listed here (https://www.sheldonbrown.com/retroraleighs/) you can probably identify your bike and learn its original specifications.

Here is a 1990 catalog which definitively states the road bikes use 700c tires.

Maelochs

Here you go---pdfs of a lot of Raleigh catalogs. Look for your bike, see what is came with. ---https://labibleduvelocataloguesraleigh.blogspot.com/

I see that these are just the race models ... I think there might be different catalogs .... whatever. If you check the serial number and it is 1985 or later it is probably 700c from the factory.

Okay ... it looks like 1985 is the year Raleigh went to 700c. https://labibleduvelocataloguesralei...eigh-1985.html

kghowell1765

Hi, Thanks. greatinfo.

Looking at the bottom bracket, the number are "3AR074" . Under that series is a "N"
Its a Competition model.
I was expecting 700c so I was surprised to see the 27s.
Having said that, it really deosnt appear that there is any adjstment left to move the pads down further.

Ken

dedhed

https://www.kurtkaminer.com/1983raleighcat_us_10_lg.jpg

​​​​​​https://www.kurtkaminer.com/1983raleighcat_us_34_lg.jpg

KerryIrons

Yes, because after all the width of the tire is essentially its diameter. Given a larger circumference from a larger tire, some very old geometry proofs show that increasing width is the same as increasing diameter.

wheelreason

So a 20x2.0 has the same diameter as a 26x2.0? On what planet?...

Ironfish653

Diameter in the axial plane, not the radial. The profile of tire is essentially a circle, sitting on top of the rim; if you were to view it in section. A wider tire would also be taller (from the rim bead to the tread) when mounted on a given rim.

​​​​​​Don't be obtuse.

wheelreason

Yeah, except we are discussing reducing the total diameter of the wheel not the tire Warden...

Maelochs

Oi .... there are so many of us let's have a war!

macattack71

I have a 1987 Raleigh Technium 440 12 speed that came with 27" Araya rims and 1 1/8" tires. I could mount 1 3/8" tires on my bike, but mainly ran 1 1/4". Have since gone to 700C wheels with 32mm tires and changed out the brakes for some longer reach ones. And upgraded to Tiagra 4600. Its so much more usable now.

kghowell1765

thank you. Upgrading to 700c is a great idea but for budget reasons it will need to wait. Sounds like it worked very well for you.

kghowell1765

Thanks for this info. It definitely looks like the bike in the pic. Same paint job too. I'd love to get ahold of the gum rubber hoods on the brake levers.

VegasTriker

Your bike has Shimano cranks, BB, and chainrings. That means there will be a date code on the inside of the cranks. It is easy to find as it is a simple two letter code stamped into the cranks with a circle around it. Then go to one of several sites that have the code versus year and month the part was made. This site shows some of he places you will find the code in addition to the code on the cranks. It's a pretty good guide as the bike was likely assembled not long after the parts were made. https://www.pedalpedlar.co.uk/blogs/...ano-date-codes

Darth Lefty 

This really does hinge on what year the bike was. A fancy training and racing bike from the 70's into the early 80's will be able to take 27 clinchers, or 700c tubulars with fenders. A plebe would keep it on the 27's and a bike nerd would change them for tubulars. (This is discounting "sport touring" bikes which had more room.) By 1990, pretty much only touring bikes and tandems were coming with 27's. A training and racing bike from 1990 is likely to be really close fit with 700's and never meant to see 27's.

The story is attractive that someone - either thirty years ago or thirty days ago - tossed in a 27. That doesn't explain why you don't have any more brake reach left, though. How far back is the axle in the dropouts? Does the front wheel match the rear? Does the front brake match the rear? Do either of them match the catalogs once you get the year figured out? The crankset is the most likely piece to still be original as it's the one that you can't take off with auto mechanic tools. Then see above about Japanese date codes. Is it shifting ok into granny gear? A a racing/training bike would have pretty short shifts and its derailleur might have a hard time with an average bike boom ten speed wheel with a larger granny.

dedhed

https://www.bikeforums.net/classic-v...mber-help.html

Rick_D

Yes, especially if you keep it to the same brand. I have found across brands that e.g., Brand A's 700X35 can sometimes be as wide and tall as Brand B's 700X38. Which is annoying as heck if a purchase based strictly on stated size proves to not clear the bike.

Hope you get on the road, soon!

KerryIrons

Oh, man you got me! Here I mistakenly thought we were talking about the effect of changing tire width on a given set of wheels, but you saw right through that and realized that the OP was planning to change wheel size and wanted to know what the impact of that would be on tire height fitting in his frame. Good on you for catching that! I now feel SO foolish for missing that. Either that, or you were just creating a completely false argument and then scoring points by winning that argument.

kghowell1765

I hope so too. Thanks for the reply and info.

kghowell1765

Hi. The axle is all the way in the dropouts.
Yes, everything matches and based on some specs posted by another person, it all appears to be original.
The front wheel is not rubbing at all, just the back.
Thanks for the info.