Thursday 31 October 2013

Frozen handlebar stem


I bought a 1982 Hirame Model 48 SUMA bicycle frame a couple of years ago on e-bay, which came complete with a frozen handlebar stem. Hirame were made by Kuwahara, from Osaka, Japan and imported into the UK in the early 1980s, by the now defunct bicycle business Evian (G.B). The frame had been used as a winter bike, judging from the nature of the corrosion and all the gear tunnel braze ons and rear gear hanger had been removed from the frame. It was no longer in the original paint. My frame is not from a top of the range machine built with Ishiwata tubing. It was my intention to restore the bike to as near original as possible, with all Japanese parts. The frame originally had full chrome forks and rear dropouts. The difficulty was how to remove the original alloy stem which was stuck in the frame due to galvanic corrosion? I intended to try and save the stem if possible. It would be easy to cut the stem and melt the seized part out of the steerer tube with a gas torch. I had done this in the past and read of various methods on web forums, of how to remove the stem, but all involved the destruction of the alloy stem. I preferred to try a different method. Making sure that the expander bolt assembly was in the stem and tightened up, I up-ended the frame and hung it over a drip tray. I then poured a product called Plus-Gas, down the steerer tube, leaving a small reservoir above the expander bolt and left the frame for three weeks, refilling from the drip tray as required, adding some new liquid each time. Once the liquid had finally drained out of the steerer tube, I then righted the frame and inserted a front wheel into the forks. I then released the stem expander bolt and inserted a used, salvaged, long steel riser MTB handlebar into the stem to try and turn the stem.

It gave easily and with a little effort, levered out of the frame. There was much evidence of galvanic corrosion, especially in the slot at the back of the stem above the shaped expander nut.



I cleaned the alloy with a brass brush before using a metal polish. There was a linear crack spreading horizontally, each side of the circular hole at the top of the slot designed to prevent cracking!
I would guess the damage maybe occurred when someone tried to remove the stem, whilst it was welded in through corrosion, prior to the frame being sold. I am disappointed that the stem is not safe to re-use, but it was worth the effort to try and remove it in a non destructive fashion.  I have learned something along the way.   I don't know if this method will work in every case, but I will certainly try it again in the first instance, to try to remove a stem without damage, before resorting to a more destructive method of removal as a fall back position.

Wednesday 9 October 2013

1925 Raleigh Roadster


It is one of the dilemmas that any collector or restorer of old bicycles faces at some stage, to restore or not? I received a 1925 Raleigh bike for some repairs last year. The bicycle had great sentimental value to the owner. It had belonged to his uncle from new and had been his uncle's main form of transport for most of his working life. The bicycle had been ridden at least 44 miles return journey, daily to work, carrying his tools and his 'piece'. The wheels had been renewed in the 1950s judging from the date code on the Sturmey Archer hubs. This would equate to a major overhaul of the bike and probable conversion to a three speed gear, from single speed, after roughly 25 years of use.  The rear wheel was a quality Raleigh product, 40 hole stainless steel Westwood rim, laced with stainless steel spokes into a Sturmey Archer AW hub. The front wheel was a very rusty chrome Westwood rim, laced with equally rusty spokes into a Sturmey Archer GH6 dynohub. 

My concern was to try and keep as much of the bike original as possible, but it was obvious that the hubs were in need of some attention. The bike was covered in a black oily filth which had protected the chrome plating on the hubs. Once the rear AW hub was opened, it was one of the dirtiest I have ever had to strip.

The component parts all had to be thoroughly cleaned to be able to assess the extent of the wear. What was obvious, following cleaning, that the cones were badly worn, along with the driver and ball ring. The springs all needed replacing as well. The axle threads were also very worn, but as the bike was only to be used occasionally, I decided to keep the axle as the sun pinion teeth were good. New parts were fitted and the hub internals re-assembled and lubricated. Once the completed internals were refitted into the hub shell, it was obvious the new parts had not removed all the play from the bearings. The left hand K517 ball cup was obviously very worn and tired from the heavy mileage it had endured. To top it all, the threads stripped on the axle when putting the wheel back into the frame. I wanted to keep the back wheel, so the AW was stripped down again. The left hand ball cup was removed after some reluctance.

A suitable spanner was used with an 'enforcer bar' to increase the leverage, so as to overcome the reluctance of the ball cup to screw out. A new old stock K517 ball cup was fitted after the hub shell threads had been thoroughly cleaned then greased. The hub gear internals were then stripped down again and a new axle fitted and the unit rebuilt. This was then inserted into the hub and quickly and easily adjusted. The indicator rod was then refitted, before the wheel was put back in the frame. The gear cable was then refitted to the indicator rod and adjusted so all the gears worked. I next started on the front wheel. The rim and spokes were both badly corroded. In addition the rim had a number of flats. I stripped the dynohub down to check the hub shell ball cups but these were worn out too. 

It was a case of find a replacement hubshell, fit new cones and refit the dynohub internals into the replacement hub shell. Once this was done, I built the hub into a new 32 hole 28 inch Westwood rim.
It was also necessary to fit a new front tyre. The new wheel was then refitted to the frame. I also fitted a new front mudguard at the request of the owner.
The bike was taken for a run to see that the gears worked properly. The headset and bottom bracket were both worn, with some play in the bearings, but this didn't have any adverse effect of the handling of the bike. Although very heavy by modern standards, the bike was actually very nice to ride unlike a modern heavy steel mountain bike. The bicycle felt lively and responsive to the pedalling input once the initial momentum had been gained. I can see how people toured on these roadster bikes 80 to 90 years ago. Although, not considered by some veteran bicycle aesthetics as being worth bothering with, who disparagingly refer to these machines as 'nondescript', due to the fact they were mass produced in a factory. These machines may have a low monetary value and lack the perceived cachet, or one upmanship of a rare brand or hand crafted bespoke frame, which some of these self appointed guardians, of taste and historical worth, espouse.  However, these humble machines do relate, very much, to social history. As the ordinary working man's transport before mass car ownership, they represented a considerable investment by the owner and were usually bought through the cycle manufacturer's hire purchase scheme, via their cycle agent. Their survival after decades of storage is an indication of the value in which they were held by their original owners. Where the history of a particular machine and it's owner is known, this can often open a historical window into the working and recreational life of the former owner.  As this machine predates the opening of the Raleigh factory in Dublin in the late 1930s, after which Raleigh increasingly had the lion's share of the Irish bicycle market,  the owner obviously made a conscious decision to purchase his Raleigh in a more varied and competitive bicycle market. It is now getting more unusual to find pre WW2 machines, as many older machines were scrapped as part of the wartime metal salvage campaign.  It was good to return an old veteran back into a rideable machine again.