My car won't fit in the garage since arrival of a 2nd bike (my NC30) almost 18 months ago, thinks I may as well buy a 3rd! ...much distain from the mrs

Having enjoyed fiddlin' with [& very much ridin'] the NC, I thought I'd have a go at a non-runner. So In a moment of madness I bought this off eBay for not a lot without viewing it ...thought that if i can't get it to go then there is the option to break it & sell the parts. So here is my GSX-R400 GK73a





No history except problem with carbs and not run for 2 years. The photos are very kind, fairings are quite tatty in places. Gold wheels which are very good. It has standard rear shock (with no resevoir) so assume the SP rear end is cosmetic addition to a std bike (overview in doc section states suspension & gearbox should be different). Any other differences or pointers welcome. It has some issues, the front forks are odd, i.e. not a pair, LH is standard but RH has extra adjuster screw on top & rear facing adjuster near bottom of leg? Both fork seals are badly fucked anyways so would need to be sorted. Also there appears to be a botched repair on the cylinder head at 2 exhaust ports, I've not inspected it thoroughly but I believe it is likely to need a replacement head. The rest of the bike seems to have been fairly well preserved under a generous layer of crap.

I have realised that i'm a LOVER not a BREAKER at heart, so hope to bring it back to life... if it doesn't prove to be a complete money pit [quote from the wife: confirmed I am a hoarder of junk]

Info a lot thinner on the ground on this bike but been doing lots of reading & collecting useful stuff from the document section, forums & hinternet. Could benefit from a descent manual in english & microfische/good diagrams really, as not good with Japanese. Made a start stripping/inspecting some parts, but likely to be a long term process due to time & money constraints. Will take some more detailed pics of damage/issues when I get to them.

Refurbing a descent 2 bike galv trailer to replace my homemade single one at the mo & got loads to do to the house this spring. Kinda set myself a goal of taking it to the Cadwell meet in August but i'm notoriously rubbish at deadlines!

Good luck. Looks to be a fairly honesty bike. Nice reg too

Cheers, underneath has lots of medling so god knows what i'm going to find. Reg is sweet, hope it brings some good luck with it!

Further reading of the manual (bit on R400FJ 1988 SP), shows I have a mix of parts. Likely to be standard bike with an SP RH fork, rear fairing & seat unit. Assume I should plump for finding an LH SP fork due to the rebound adjustment. Will need to look at the motor first though.

Plan A was going to attempt to get it running first before deciding what to do with it but that was before I knew about the head exhaust port damage, it could be too risky to attempt to start it and even if successful would need to be stripped anyways. Its not seized but I have not rotated the engine fully either yet. Gears all seem to select ok. Indicated mileage is only 18000km (no idea if this is genuine but I tend to doubt it). Really don't want to do a full engine rebuild unless absolutely necessary. So I have concluded best go with plan B:

My thoughts:
Drain engine oil & inspect
Remove engine dismantle top end and see whats what.
Replace head
Inspect sump contents
Service carbs

Anyone got a spare cylinder head going begging?

Is it correct that head from a GSF 400 bandit (head pattern no 771502) is compatable/the same?

Nice little project you have got there mate, the gk73 is the best of all the GSXR400's so your allready ahead. Id say that your right about the fork being an SP item but the seat unit looks stock with a seat cowl, SP seat units need to be cut to fit pillion pegs.

Not sure if the heads are interchangeable with the bandit, but there are loads and loads of parts that will swap over between the models its just a case of finding out which ones do and dont.

If i find out my old external hard drive i have a load of documents and info saved on there about the GSXR 400's i will send them over, alot of it is only relevant to the gk76 but im sure theres a few bits and bobs of useful info in there that i found after trawling the internet.

You shouldnt struggle to sort out the carbs, the 73 ones are a much simpler design than the 76's so much less to go wrong and no bloody orings that perish every few months, a good strip and clean will sort them out i should think.

Keep us posted mate.

Thanks.
Learning all the time. Regarding the seat unit I think you are referring to the revised 1989 SP. Sussed that the rear of mine is from a 1988 SP which is identical to standard fairing (except for SP decals & cowl).

good stuff! I'm sure I spotted this on Ebay in south Wales, Cardiff?
what's up with the head, broken off studs?

Been real busy with work & stuff on the house of late, so havent really got going on it yet.

It was in Kent. Seems broken bits of head casting have been botch repaired with what looks like araldite. As a result I have no faith in state of engine so intend to take engine out and remove head to assess damage properly, including rest of engine whilst i'm about it. Exhaust bolt heads look overly big so guessing theyve all been helicoiled. Checking the parts manual it seems a bit odd that Suzuki use bolts rather than studs. If I do replace the head then I think I will use studs instead.