NRCD 1982 Suzuki GS850 restoration

Posted by Shane Newman on



Bike was a farm find, and had not been started for 15 years.

Why a Suzuki GS850? : Well I believe the GS850 to be an under rated classic sleeper.

Yes, a heavy bike but solid, surprisingly nimble, no frills reliability with one of the best designed, strongest shaft drive units to date. The engine, a clever upgrade to the already tried and tested 750cc variants with an enjoyable amount of power. The later models having very good Mikuni CV carburettors. 

Too many of the chain drive 80's GS Suzuki projects, sellers are asking big money, the GS850 has a beautiful shape and is currently very affordable.

The design line from the dash down through the tank and seat has a lovely flow. I believe the GS850 to have one of the best shaped Japanese classic tanks around, large but sleek slung over a tough tubular frame and is already a top contender for any well to do café racer /brat build.

The Suzuki GS850 engine is a very strong, bullet proof design. A well established second hand parts market exists and the GS850 is a bike you can ride eight hours straight and not have to be lifted off with a crane at the end.

The bike came fitted with a Harris works exhaust and after market seat , not cheap items back in the day and over all, was in pretty good shape, albeit just covered in grime ( the grime actually protects the engine and final drive casings ~ grime is good, we like oily grime )

The bike had ok compression, spark and ran on the remote fuel tank. The bike would only idle with the choke on full, any throttle response and the bike would stop.... Dirty jets, blocked choke pathway ( very common on the old Mikuni carburettors.)

* Make a to do list, parts, tools, consumables ( not biscuits.... more like, carb cleaner, clean rags etc )

* First job was to sort out the blocked jetting issue, so disassemble the carburettor bank, sonic cleaning bath the lot and ordered new pilot and main jets.


* Sonic bath or ultrasonic cleaner, I use a 50/50 mix of GUNK and water, you can also use Simple Green or similar biodegradable engine degreaser. 50 degrees Celsius. A ten litre bath fits a three carb bank, so just remove the end carburettor.

* Important, if CV carbs, you must remove the slides and rubber diaphragms from the carburettor tops. The high vibration from the sonic bath with rub straight through the thin rubber diaphragms especially if they are old.

At some point, a heavy handed tool user has stripped the brass jets, I wanted to make sure the correct jets were fitted, so had to carefully drill out the old ones. This is a delicate job, the drill bit is approximately only 3mm wide, if you slip or drill to far, you will write off a good set of original carburettors. Take your time, especially if you do not own a drill press and are free hand drilling.

Either way, the carbs must be soft clamped firmly, you can not have any unwanted movement at all. The process is like fine surgery, a one shot deal.

Clean bench, clear head, the right tools. Don't rush ahead, if you are unsure of what to do, get help and wisdom from someone who has done the work before. Watch YouTube videos, get as much knowledge as you can prior to the job.

* Carbs in, new main jets and pilots , other parts inspected and reused. New engine oil. Set to factory settings at 3 turns out on the air screws from seated.

* Important, if a bike has been sat for a long time, only attempt start up with fresh oil. Even if the seller tells you they put fresh oil it again. It guarantee's you have fresh oil and the correct oil and new oil filter.

Remove the spark plugs and crank the starter a few times to get oil up to the cams. You can remove the rocker cover and inspect that clean oil is circulating if unsure.

* Starter motor rebuild, its easy, affordable and peace of mind.

Clean and new bush kit installed.


* Stuck clutch. Removed, cleaned with fresh fuel, soaked over night in fresh engine oil then re installed with a new gasket and thin layer of gasket paste.

*Tip : Apply a thin layer of gasket paste with a small modelling brush as added sealing capacity on old gasket surfaces. Trim the excess off with a razor once cured.


* Once happy with the engine, I then moved onto the electrics. Only thing of note was the dash bulbs had blown in the gear selector display. Tiny filament bulbs, bound to happen. I also wanted to upgrade the 1982 coils to a more modern coil.

* Hitachi Suzuki bandit 600 coils, brand new, good quality and price , easy fit , sorted.

Top picture, the new Hitachi coils

 Bottom pic, old coils

* Front brake master cylinder had no brake fluid and after removing the cap, found it full of rust. Again, the trusty sonic cleaner, a seal rebuild kit and good as new. I also did the same for the rear and front calliper's. Front forks had no oil leaks, the seals had covers and were in good condition. I ran a fork seal tool under and around each seal, then changed the fork oil for fresh 10W.

* Tip: Believe it or not, most leaky fork seals are due to contamination of debris under the seal sealing edge. You can avoid costly repairs by investing in a cheap seal cleaning tool, or make your own ( videos on Youtube ).


* Tyres, suspension and brakes are what save us riders should anything go wrong, so please if you are restoring bikes or flipping for a bit of coin, make sure the bikes are sold with good tyres, brake pads and brake components or, at the very least, let the new buyer know they need to be done.

* Chrome and alloy cleaning tip : Degrease, then tin foil and water. Just dip some scrunched up tin foil / silver foil in water and begin rubbing that pitted, rusty chrome work. It really makes a difference.

Here is the new oil pressure gauge fitted and the engine cleaned, any chewed out bolt heads were replaced with new stainless steel and spring washers.

*Having parts hard chromed is expensive, depending on how far you want to restore the bike, oily rag restoration is the most cost effective on desirable but not overly expensive motorcycles. Suzuki used many of the same parts on different models, so if you are lucky , you can pick up really good quality second hand parts for a great price, transforming the look of your restoration project.

Plastic repairs and paint work:

I am a qualified automotive spray painter. You can save a huge amount of money by painting your own parts. If you do not have an air compressor setup with spray gun, you can get by with 2K rattle cans like SprayMax. The great thing about bikes, they are small and do not require a lot of product.

* Always go 2K for epoxy primers and top paint. 2K is super resistant to road grime, petrol spills and the clear coat is long lasting, it is what the automotive industry use on new vehicles.

* An amateur mistake is to use rattle cans on petrol tanks, then cry later when gas gets spilled at the fuel pump and that beautiful paint finish that took days to complete, washes down onto the forecourt. SprayMax cans are a good cost effective way to get a professional finish easily, the spray nozzles are very well designed and the paint is high quality. 

* Remember, a paint job is only ever going to be as good as the surface it is sprayed on and the environment it is sprayed. Spend more time on the preparation and create a dust free environment; we want that paint finish to last 20 years . There are videos on Youtube covering the use of SprayMax cans and also full air compressor spray painting.

Plastic cover take a hammering, grind out any cracks and then plastic weld.

Tip: Silicon paste on the side cover securing rubber grommets makes covers easier to remove and fit resulting in less flex.

Epoxy primer

Paint I chose was a non metallic burnt orange



I really hope you enjoyed this Suzuki GS850 " engine in frame " restoration. I really love the Suzuki GS850. The exhaust, seat and modern paint gave it the custom look but at the same time keeping it tasteful. I knew the bike was safe, well maintained and was a joy to ride. Bike was sold within four hours of posting the advert and it was great to see the new owner ride away knowing I had saved another bike.

For me, I really enjoy the build, returning life back into the old girls.

Every build puts me in contact with bike owners, bike clubs, bike forums and folk who love these bikes. It has been an honour and a privilege. Thank you.


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