'73 Suzuki GT250 - Part 6 - '79 Suzuki RM 125 rear wheel refurbishment

Since I’m using a ’79-80 RM/PE 250 swingarm in my GT250 I figured that it would be easiest for me to fit same type of rear wheel to go along with it. I made a want-to-buy add to our local vintage MX forum requesting a ’79-80 RM250 rear wheel.

I had almost forgot my add when I received a phone call from a guy nearby. He had a pile of parts from a ’79 RM125 for sale including a rugged rear wheel, which would acquire quite a lot fixing up. Rim on it had cracked from several places and spokes were warped. After being outside for couple of decades lots of rust had formed in the brake drum and bearings were seized in place. 

'79 RM125 rear wheel (right).

Disassembling was the first thing to do and getting the beat up tire out with help of couple of tire irons and some lubricant. I needed to save few of the spokes and nipples so I applied some rust remover to them, screw them out with a spoke wrench and marked them masking tape. I removed the ones that were badly jammed or had cracked nipples with an angle grinder. Bearings were easy to get out after heating the housings with a hot air gun.

Couple of tire irons, spoke wrench, 1 mm cutting disc
for angle grinder and rust remover.

Rear wheel hub, bearings, spacer, spokes and nipples.

Rear wheel didn't come with a brake shield so I bought one from eBay and disassembled it.

'80 Suzuki RM125 rear brake shield

Due to heavy use and load bearing housings on the sprocket side tend to wear out and become loose. One way to fix this is to turn the housing bigger and fit a new steel bushing to it, which then holds the bearing. I send my hub to a machine shop located in Kokkola, Finland, called Konepaja Ågren to get it fixed up.

Pair of 6202-2RSH/C3 rear wheel bearings (15 x 35 x 11 mm).

I marked the worn bearing housing with a red marker pen.

Fixed housing with a new steel bushing inside.

Once I had both rear wheel hub and brake shield I masked them for sandblasting. I used old parts (rear sprocket and bolts, caps etc.) and masking tape to protect surfaces I didn't want blast. I also cleaned the brake drum before blasting with rust remover and a sanding pad. I took blasted parts to one of my local paint shops and got them painted black.

I used old parts for masking to protect surfaces I didn't want
to get sandblasted.

Painted rear wheel hub and brake shield.

I cleaned the brake drum with rust remover and a sanding pad.

I was looking for a new rear wheel rim and I got an offer of a new old stock (NOS) 18" x 1.85" Takasago rim with 36 holes. Since it had a reasonable price I decided to purchase it. Surface of the rim had stained during storage so I cleaned it with some Autosol Metal Polish and Autoglym polishing cloth.

NOS 18 x 1.85 Takasago rear wheel rim.

Storage stains on the surface of the rim.

Autosol Metal Polish and Autoglym polishing cloth.

Surface after polishing.

I picked one inner and one outer spoke from sprocket and drum brake side of the hub (4 total), marked and send them to Wheel Factory Finland, a company which makes custom spokes and nipples. I decided to try stainless steel spokes in this project. I've used their spokes before on couple of my bikes and been very pleased with them.

Model spokes marked and ready for shipping.

New set of stainless steel spokes and nipples.

Dimensions for '79 Suzuki RM125 rear wheel spokes.

I assembled the hub (bearings and spacer) before putting on the spokes. I used an axle seal (20 x 35 x 5 mm) to cover and protect the sprocket side bearing. I will turn a new bushing for it when I start lining up front and rear wheel sprockets.

New axle seal (20 x 35 x 5 mm).

I began lacing by placing all of the spokes to the hub, lubricated every spoke thread with boat tar and screwed them to the rim with nipples. Once I had the whole wheel together I took it to my local village shop. They do lacing for bicycle wheels and were able to line up my wheel and tighten the spokes for a fair price.

Bottle of boat tar.

I lubricated all of the spoke
threads with boat tar. 

Assembled rear wheel.

I've wanted to try white vinegar for rust removal for a while and brake shield parts seemed suitable for this experiment. I set rusted parts to a plastic container and filled it up with white vinegar. Placing the container to a warm location sped up the chemical reaction. Vinegar quickly turned to brown color and after a while to black. Unfortunately after keeping the parts a bit too long in the solution it had build up a black gooey layer on the surface of every part. I cleaned it off with warm water but it left black stains, which I had to soda blast off.

Rust removing with white vinegar.

Parts after white vinegar treatment...

...and after soda blasting.

Now that I had rust free parts I decided to try bluing them. I bought a bottle of Birchwood Casey's Perma Blue, a liquid gun blue. Bluing is simple process, which starts by applying the solution to surface of cleaned and rust free parts. I used a small paint brush. At first the surface turns black for a while. After the solution dried out off the surface I washed it with warm water. Last step was to oil the surface to bring back the black color.

90 ml bottle of Birchwood Casey's Perma Blu

First three stages of bluing: rust free (bottom),
applied (center) and dried and washed (top).

Dried parts after applying bluing solution.

Oiling the surface brings back the black color.

Lastly I replaced some of the worn parts with new ones. I ordered a new OEM bushing (09319-10008), washer (08211-15341) and pivot dust seal (61262-22A00) through my local Suzuki parts dealer. I bought a new TA2225Z roller bearing (22 x 29 x 25 mm) from eBay for a more reasonable price than the OEM one. Unfortunately the new bushing didn't match with the original spherical plain bearing so I have to find another one or use the old one instead. I also bought a pair of EBC S 617 brake shoes.

Bushing (09319-10008) didn't match with
the original spherical plain bearing (left).

Pair of EBC S 617 brake shoes.

MP 17 Motorcycle Show - 3rd of February 2017 - Helsinki, Finland

The Friday before last Friday I made a short one day trip to Helsinki to visit this year's MP 17 Motorcycle show held in Messukeskus, largest venue in Finland. You can find more information on the show from its website and Facebook page.

I started my journey from coach station of Oulu where I took a night shift bus to Kamppi, shopping center in the center of Helsinki. After travelling little over eight hours my bus reached its final destination. From Kamppi I had to take another bus to Pasila, where the show took place. Before doing so I took a short walk around downtown and went sightseeing since I had some spare time before the show started.

My journey started from Oulu Bus station

Swap meet at Paviljonki, Jyväskylä - 14th of January 2017

Yesterday I made a one day trip to Jyväskylä to visit an annual motorcycle and moped parts swap meet. My trip started at 6 am when I hopped into a bus in bus station of Oulu. Tour to Jyväskylä took around four hours and I arrived at the local travel center (bus and railway station) around 10 am. 

Paviljonki, where the event took place, is located near the travel center. After drawing out some cash I crossed a bridge over the nearby railways and walked couple hundred meters to the venue. Inside the venue were three big halls full of different stands pitched by private persons, societies and part vendors. 

I was hoping to find something interesting to my GT 250 project, but nothing really catched my eye. I ended up buying one book about barn finds and a steel mug as a souvenir. Overall I had a really fun day. There were a lot of interesting motorcycles, mopeds and parts for sale.

Yamaha RD 350 F2 '88 - Part 8 - Farewell

Sold today my '88 RD 350 F2, which I had for sale approximately two months before finding a new owner for it. It didn't leave too far so hopefully I will see a glimpse of it on the road some day. I was already planning to do some modifications to it in the near future but now those ideas have to be bypassed.

New owner of the bike showed me a nice picture of his collection of older RD's, which was missing a newer liquid cooled one. He already had plans for an engine rebuild, which definitely would have been on my to do list also for the upcoming winter. All in all my now ex RD found a good home so I was happy to let it go for a fair deal. Now I will try to concentrate on getting my GT250 project finished.

'73 Suzuki GT250 - Part 5 - '79-80 RM/PE 250 swingarm swap

Here's first part of fitting '79 RM 250 swingarm to my '73 GT250, which at the end was a pretty easy task. Hardest part was to find all the necessary bushings for it since I didn't want to lathe them myself. I started by ordering a pair of new old stock swingarm pivot bushings (61261-40402) from eBay, which I knew I was going to need. 

Pair of Suzuki swingarm pivot bushings (61261-40402).

Next step was to find proper bushings inside the pivot bushings and bearings. After a bit of googling I came across a Kymco scooter speed up kit made by Naraku (NK800.04). Since I knew I needed bushings with 14 mm inner diameter and 20 mm outer diameter, that kit seemed like a perfect match and I ended  up ordering a pair of them. They are approximately 38 mm long (37.94 mm to be exact) so I needed a spacer which would keep them a part. I ended up lathing 113 mm long spacer out of 19 x 1.50 mm steel pipe.

Pair of Naraku Speed Up kits (14 x 20 x 38 mm) for Kymco
(NK800.04).

Lathed spacer (19 x 1.50 x 113 mm).

Once I knew how long all the bushings were I could order proper sized needle roller bearings from eBay. I decided to go with IKO TA2025Z, which are 20 x 27 x 25 mm and have open ends.

(3) Pair of IKO TA2025Z needle roller bearings with open ends
(20 x 27 x 25 mm).

Stock GT250 swingarm axle and all the new parts.

Test fitting.

I had to narrow the swingarm a bit so it would fit better with the frame and bushings. I took a bit of material out of both sides of the swingarm with a file and a sanding block. I also made the swingarm a bit narrower than the inner bushings. With a bit of clearance the swingarm swings smoothly once the swingarm axle is tightened. 

In the second part of the swingarm installation I will cover how to fit rear shock absorbers and modify their upper mounting points. But before that I have to refurbish front forks and fit them to the bike. By doing so I can check the stance and figure out how long rear shocks I need to order.

'73 Suzuki GT250 - Part 4 - Removal of broken swingarm bearings/bushings

I might have teased you in my last post that I was going to show how I fitted that aluminum '79-80 Suzuki RM250 swingarm to my '73 GT250K. But before we do so I wanted to write a little post on how to easily remove old swingarm bearings/bushings with simple tools, which you can find from almost every garage. 

Here's a little backstory about the swingarm. A while ago I bought a swingarm from '80s RM/PE250 through a want to buy add, which I had written to one Finnish classic motocross forum. It didn't take long to receive an answer for my it. Seller of this swingarm was from southern Finland which meant that I had to purchase it without seen it first. He send me a few pictures of it but nothing too detailed. Once I received the shipment I noticed that it had broken bearings or some sort of bushings inside the bearing housings. For a while I had to figure out how to get them out of there. In the end the solution was pretty simple.

'79-80 Suzuki RM/PE 250 swingarm

Broken swingarm bearing/bushing.

Bearing housings in this swingarm have 27 mm diameter. This meant that I could use M8 fender washers (24 mm outer diameter) to pull both of the bearings/bushings out. I had to grind few of the washers to make them narrower. This helped to slide them through one of the bearings/bushings and set them behind one of them. After that was accomplished it was easy to pull bearings out with a long M8 bolt and 27 mm socket.

Long M8 bolt, nut and fender washers.

Narrowing few of the washers helps to slide them through 

bearings and inside the bearing housing. Use them to get the 

first bearing out of the way.

27 mm and 13 mm sockets, small ratchet and open/ring spanner.

DIY puller.

Ready to pull.

Bearing almost out.

Job done.

Broken bearings/bushings out of the way.

'73 Suzuki GT250 - Part 3 - Fitting aluminum Yamaha MX fuel tank to frame

Idea for this build started from this fuel tank, which had been for sale for a while in one Finnish spare parts advertisement website. I contacted the seller by phone and we settled a deal for the tank. He wasn't sure of the tanks origin. I believe it's originally from a Yamaha MX. Once the deal was done it didn't take long for it to arrive by mail.

Aluminum Yamaha MX fuel tank.

Once I got it I noticed that the rear mounting bracket of the tank was broken. I removed the remains of it with an angle grinder and a sander. I cleaned the area below the old bracket with a sandblaster and a piece of sand paper. 

I made a small bracket out of 3 mm aluminum sheet and bend it to a shape of a trapezoid. I finished it by filing a stadium shaped hole to bottom of it. Since I wasn't able to weld aluminum I visited Mikko from Speedhouse and he welded the bracket for me for a small reward. Mikko builds and maintains motorcycles for a living. You can find few pictures of the bikes he has build from his website: http://www.speedhouse.fi/albumi/pyoria/. 

Tank didn't came with any locating dampers so I had to order a pair of them (3TB-24181-00) from one of my local Yamaha parts dealer. Once I had them it was easy to design a front mounting bracket for the tank.

Tank had a broken rear mounting bracket.

New one is made out of 3 mm aluminum sheet.

Pair of locating dampers (3TB-24181-00).

Underside of the tank.

I started making the front mounting bracket by bending a suitable rounded shape out of approximately 80 mm wide steel sheet. I used 2 mm thick mild steel for two reasons. First one being formability and second structural strength. I made small bevels to both sides of the top plane of the bracket. That made sliding the tank to its place easier. I tack welded two thin pieces of sheet metal inside the bracket to keep the tank from moving sideways. Once that was done I tacked it to the top tube of the frame. 

Finished front mounting bracket.

Side view.

Bracket tacked to the top tube of the frame.
Seems like I forget to remove mill cinder before welding.

Rear mounting bracket of the fuel tank needed a counter part, which I cut out of flat bar. I drilled a hole to the center of it and tacked a hexagon weld nut to the bottom of it. Once I figured the right angle for the tank I tacked the piece to the frame. I didn't want to weld either of the brackets definitively. If there's going to appear any fitment issues in the future, for example with triple clamps, it's easier to move their position.

Counter part for the rear mounting bracket.

Both brackets tacked in place.

Test fit.

Next time I'm going to start fitting the aluminum RM/PE 250 swingarm, which you can see in the background. Stay tuned for that next week!

'73 Suzuki GT250 - Part 2 - Mount for '87-90 Honda CR250 rear fender

Some of you might caught your eye to the small piece of flat bar welded to the rear part of this bike's frame. I made that bar to work as a support bracket for the rear fender I bought. For a while a had search for a proper rear fender. I started by going trough a catalog of Ufo Plast plastics. Rear fender for '87-90 Honda CR 125/250 (UFO-HO02601061) caught my eye and seemed like an easy fit since it required two pieces. I contacted few persons who were selling subframes for '87 Honda CR 250 on eBay and asked some key measurements. Luckily dimensions matched and I ended up ordering one from my local motorcycle parts store.

'87-90 Honda CR 125/250 rear fender
made by Ufo Plast (UFO-HO02601061)

Once it arrived I started making a support bracket for it. I made a simple template out of wood and bent a short piece of flat bar against it. I chose to use flat bar since it is pretty easy to bend just by hand. Even with mild steel there's always a little bit of spring back so you have compensate it by overbending. Once I had a rough shape I cut it to right angle with an angle grinder and welded it to the frame.

Piece of flat bar bent to shape and welded to the frame.

From a different angle. 

Last thing to do was to drill holes for fasteners and tack a pair of hexagon weld nuts on the bottom of the bracket. I chose to use M8 sized ones since I had them in stock. I still need to drill holes to both sides of the rear fender, but I will do that later.

Pair of M8 sized hexagon weld nuts.

Tightened in place with hex screws and ready for welding.

Underside view.

Hexagon weld nut tack welded.

Top view of finished rear fender mount.

Rear fender on.

Underside view.

From another angle.