Marko's Workshop

Saturday, 8 October 2016

'73 Suzuki GT250 - Part 1 - Something different

I have always liked the look of vintage motocross bikes and been wanting to own one. Especially ones with twinshocks have always appealed to me.

The idea of building one out of a GT 250 might sound crazy and have little sense but sometimes you're just forced to use what you got. I've owned this bike for a while now. I've also slowly been collecting parts for it. First idea was to build a vintage motocross bike styled supermoto out of it, which would have been great for street use, but I ended up scrapping that idea because it would have been a bit too expensive. So instead I decided to go with vintage MX style look.

I will try to build this bike with a smaller budget. I will mainly use second hand parts for it in exception of parts which will wear I will replace. Front forks and engine will remain stock but I will build a custom exhaust for it. Swingarm is from '79 Suzuki RM250 and tank from Yamaha MX 400 (if I'm correct). Front wheel will naturally be 1.60-21" and rear wheel 1.85-18". Front hub will stay stock and rear hub is coming from '79 RM125. I will get new laces made for them. Custom parts like seat, inner rear fender and airbox I will need to fabricate myself.

'73 GT250 frame and pile of vintage MX parts.

Stripped and cleaned frame.

I will finish this post with a video of Iain Clark's '74 Maico 400 made by Chris Montignani, which has inspired me a lot regarding this project. There are a lot videos of cool vintage MX bikes on Chris' channel so go and check them out also.

Tuesday, 4 October 2016

Yamaha RD 350 F2 '88 - Part 7 - Front fork maintenance

One of my RD's front fork seals was leaking oil through. To fix it I went and ordered a new seal kit from eBay made by Tourmax (FSD-002), which included both front fork seals and dust covers. I also replaced two metal slides (51L-23125-00 and 10V-23135-00) on both shocks, which help keep air inside the shock. I used same fork oil, Valvoline 10, as I used with my T250J front fork. While I had triple trees off the bike I went and greased both upper and lower steering ball bearings with a multipurpose grease.

Front fork seals and dust covers made by Tourmax.

Right front shock disassembled.
Note that there is one piece missing from this picture.
Right where the dotted line is supposed to be an O-ring
(10V-23147-00), but which is actually a washer.

New fork seals and dust covers in place.

Yankee and X-treme Car Show Lahti October 2016 - Part 6 of 6 - Cars from parking lot

And here are the last photos of my trip 😎

Yankee and X-treme Car Show Lahti October 2016 - Part 5 of 6 - Motorcycles and bicycles

Here are some of the motorcycles and bicycles which caught my attention 😎

1938 BMW R71

Yankee and X-treme Car Show Lahti October 2016 - Part 4 of 6 - Euro cars

Time to look at some of the European cars seen at the show!

Long row of BMW's from different time periods.

Yankee and X-treme Car Show Lahti October 2016 - Part 3 of 6 - American cars from 1970s and 80s

Here are couple of photos of early 1970s and 80s American muscle cars seen at the show 😎

1970 Dodge Challenger 440 RT/SE

Yankee and X-treme Car Show Lahti October 2016 - Part 2 of 6 - American cars from 1950s and 60s

Let's continue with 1950s and 60s American cars displayed at the show!

1951 Mercury Monterey

Yankee and X-treme Car Show Lahti October 2016 - Part 1 of 6 - American cars from 1920s, 30s and 40s

Last week end I made a 510 km (316 miles) long trip from Oulu to Lahti to visit one of the biggest annual Finnish car shows. While attending to the event I took lots of pictures. I decided to divide them to six different parts. Due to the amount of people attending the show it was sometimes difficult to find a suitable moment to take pictures of the most interesting vehicles. Here are photos of 1920s, 30s and 40s American cars displayed at the event. Take a look!

1926 Ford T-Tudor "Stuart Little" by Heath Garage

Yamaha RD 350 F2 '88 - Part 6 - New rear wheel bearings, seals, X-ring chain and sprockets

While maintaining rear linkage for my RD350 I went and replaced worn out sprockets and chain. The old chain had strained quite a lot during its life time and it was already tightened to its max position. One option would have been to just shorten it but since the old rear sprocket was also in pretty bad condition I decided it was best to just replace all those parts.

I ended up choosing sprockets made by JT Sprockets and a X-ring chain made by D.I.D. I went with 17 tooth front and 39 tooth rear sprockets. Since the chain needed to be riveted I had to buy a chain breaking and riveting tool also made by D.I.D. There were two types of tools for sale. I bought the cheaper one, which had "02-99" stamped on the side of it. While riveting the chain I found the lower jaw of the tool bending and had to make a cotter out of flat bar to stop it.

I also decided to replace rear wheel bearings while I had the rear wheel out of the bike. I bought a kit which also included right sized oil seal (22 x 42 x 7 mm). I used a gas torch to heat up and expand both bearing hubs in the rear wheel to get the old bearings out and to install the new ones. Depending on the condition (rusty) of the bearings you might need give them a small knock. If you have painted your wheels you might need to use another solution. If you don't have proper tools for the job, there's a lot of shops, which can do it for you.

Unfortunately I forgot to buy a new bearing (6304) for the sprocket carrier and since it was Sunday and all the shops were closed when I was doing all of this in a hurry to get the bike finished I just ended up greasing the old bearing and replacing worn oil seal with a new one (32 x 52 x 7 mm).

To sum all up here's a list of all parts needed for the job:

-Tourmax rear wheel bearing and seal kit (MCI-WBK-055)

or two 6302 bearings (15 x 42 x 13 mm) and oil seal (22 x 42 x 7 mm)

-Oil seal for sprocket carrier (32 x 52 x 7 mm)

-6304 bearing for sprocket carrier (20 x 52 x 15 mm)

-JT Sprockets 17 tooth front sprocket (JTF569.17)

-JT Sprockets 39 tooth rear sprocket (JTR846.39)

-D.I.D 520 VX2 X-ring chain with 106 links

-D.I.D chain breaking and riveting tool (02-99)

There's also one O-ring (93210-40530) in the rear wheel you might need to replace. Since mine was in good condition I just ended up greasing it.