Koga Miyata Ridge Runner (1986)

[RetroDavy]

My love of cycle touring started age 13 when I read ‘Travels with Rosinante’. That year I went on my first ‘long’ bike ride: getting the train from north Wirral to Wrexham and riding home. I still get the same sense of freedom from a long ride on unknown roads.


I still have the book

As long-distance machines par excellence, I’ve always admired Koga Miyata's superb touring and mountain bikes. I’m really excited to now have a Koga Miyata Ridge Runner frameset, courtesy of the very kind and helpful @longun who bought this from @KenG as part of a collection of frames. Chris then passed the K-M on to me, safely packaged for a trip with Parcelforce down the M62.


Just after arrival...

 

[STX-RC]

Waiting to see what's in that box...

 

[RetroDavy]

First thoughts after unpacking were that it is truly beautifully designed and finished. Triple butted cro-moly with spiral butted tubes and forks that ring like a temple bell when you flick them with a fingernail. Miyata made guns before bicycles so the spiral butting will have been a carry-over from gun barrel rifling. Low rider rack mounts on the front forks point to its touring heritage.





The 1986 catalogue shows a Ridge Runner with this paint but cantilever brakes front and rear. I guess this means they changed the 1986 model to U brake after the catalogue was printed. It also has no bottle cage mounts under the down tube, unlike the catalogue picture. There was no Ridge Runner in the range before the 1986 model year. (And thank you Koga, for keeping your catalogue archive online!)

https://www.koga.com/en/service/brochures/older-(2000-1976).htm

It must be the 21” version as it measures 50cm c-c on the seat tube, from BB to mid-top tube. They also did a 23” one. I am sincerely hoping this will fit me with the right stem and bars. I’m just under 6’ but on holiday in the Netherlands this summer I felt quite short amongst some very tall Dutch folks. Anyway, it’s got a similar top tube dimension to another couple of my mid-eighties bikes.

The frame number on this bike is NW64150. According to an Asian Serial Number database, the N means 1985 and the W the 26th fortnight, so it was made 15-28 November 1985.

https://classicjapanesebicycles.com/general-asian-serial-number-guide/

 

[RetroDavy]

Broadly, if the sizing works out my plan is to add racks and guards and go full tilt retro 26” wheel tourer: front and rear racks plus mudguards.

I'll probably build it up mostly with a 1987 Shimano Deore groupset that I have put aside. The Deore kit isn’t quite the right year or even groupset if going for originality, that would be XT. It will be close enough to be in keeping, however. Though who knows what will happen, I've not even decided on drops vs. straight / riser bars yet. There are decisions yet to be taken!

First step was to find and fit a suitably high stack 1” headset. I had a BBB cartridge bearing headset from another frame which will do for now. Nowhere near period correct but looks ok, I think, and is nice and smooth.

Before fitting the headset I weighed the frame and forks: frame is 2.6kg, forks 0.93kg.


Now fitted with a BBB 1" cartridge headset. Lugged forks - sturdy!


It's from 1986 so it has a rear U brake.

 

[STX-RC]

Fantastic frame. What is the maximum tire clearence it offers? If you are tall, maybe the best choice is to build it with a riser bar, although i prefer flat bars.
I like the idea to have front racks. This would go around the globe

 

[RetroDavy]

Fantastic frame. What is the maximum tire clearence it offers? If you are tall, maybe the best choice is to build it with a riser bar, although i prefer flat bars.
I like the idea to have front racks. This would go around the globe

It does feel like a fantastic frame. Riser bars are a good call. The Ridge Runner did come with a riser bar originally.

I've no idea about tyre clearance yet. I'll measure the frame and forks to see what might fit, tyre-wise, but I also want to know what will fit once I've fitted the mudguards, leaving a decent amount of room for mud and grit. I rode the Transpennine Trail last year on a bike with too little clearance and, on a muddy, gritty stretch east of the Pennines, had to stop several times to clear mud from between the tyre and mudguard with a plastic takeaway spoon!

 

[STX-RC]

Also the U brakes will make it a bit difficult. I like long travels, but dislike mudguards. Rather wearing those rain panties when it's dirty.
Really like that Rocinante book.

 

[RetroDavy]

A bit of progress, mainly in the cleaning department. A combination of GT85, old toothbrush, cloths, cotton buds and a cheap handheld steam cleaner (from Aldi – also good for defrosting the freezer) got all the parts reasonably clean.


Some clean parts...

Happy days, or until I tried fitting the bottom bracket. Drive side cup went in nice and easy. As did the axle and non-drive side. But then it kept going in until it was no longer projecting enough to fit the lock ring once all the play had been taken up. Hmmm. Who’d have thought Miyata would have used a 70mm bottom bracket shell!


Biopace chainrings refitted. But not on the bike until I sort the bottom bracket!

Front brake pivots greased and fitted. And a front wheel fitted to check the clearance. That tyre’s 1.95”. Reckon semi-slick 1.75” might be the biggest I can go with mudguards.


Some clearance with 1.95". But not loads.

 

[Elev12k]

Nice project. I will follow it. The bike is earlier than my '88 RidgeRunner: https://www.retrobike.co.uk/threads/1988-koga-miyata-ridgerunner.238982/

 

[RetroDavy]

Nice project. I will follow it. The bike is earlier than my '88 RidgeRunner: https://www.retrobike.co.uk/threads/1988-koga-miyata-ridgerunner.238982/

Your Ridge Runner is absolutely stunning. Really interesting thread too, thanks for sharing.