Need piston rings for 1982 gs 400 e (gsx-400)

[Rob]

Hi,

My son purchased a 1982 GS 400 E, under the premise from the seller that the bike ran great.

Well, it doesn't.

Starts fine, but as soon as it warms up, performance goes down the tubes, and last week, we had oil in the Air Box.

We have gotten to the point of determining that we believe that it needs piston rings.

The trick is trying to find the rings.

What I really need is the OEM part number for the RINGS, or if anyone has rings that they are willing to sell.

Perhaps a spare GSX 400 engine?

Trying through local Suzuki dealer, but no luck yet.

We are located in Uxbridge, Ontario, Canada

Any help would be very greatly appreciated!

Thanks so much

Rob

1982 GS 400 E

 

[Guest]

Now you're in the right forum; the preamble is in the carburetor forum for those who missed it.

Before you order up some rings, you have to make sure that the bores are still serviceable. Do you have the pistons out yet? You may need pistons and a rebore as well. Or the rings could be stuck in the grooves, broken, and so on.

As these engines were sold extensively in Europe you may find sources in Britain or the Netherlands. You may even find that a Suzuki dealer can order them - if they want to bother.

Another possibility if you get completely stumped is to find another bike with the same bore size that you CAN get rings for. I ran Kawasaki rings in my '65 Aermacchi 250 with no problems; all they have to do is fit and do what rings do.

 

[Guest]

The 67mm bore is shared with the 1979ish GS425, although the pistons are different. The Honda CB360 is also 67mm and Honda is pretty good at basic parts for their 'archive' models. But the easiest might be the Yamaha Trailwing TW200 which is still being made. That motor has been around since about the same era as the GS400 and the ring dimensions could be the same.

 

[Rob]

John Park,

Thanks for the awesome assistance.

I have found a dealer that is willing to at least assist.

However, they asked for the serial number, and they say that the "vehicle not found".

Anyways, they took my number and are assisting to get me some more info.

Did find a pooched, incomplete engine for $ 400 at a wrecker, not sure if that makes sense.

Any thoughts appreciated.

Sincerely

Rob,

1982 GS 400E

 

[tkent02]

I would almost bet that the 67mm rings on that 425 are the same part number. That's just how Suzuki rolls.

 

[Guest]

Although I've never dealt with them, here is the parts supply in the Netherlands:

classicsuzukiparts.nl

They even go by Suzuki part numbers. I think the number for standard piston rings is 12140-44110; they currently have ten sets in stock.

What you need is to download the factory manual and I'll see if I can find a parts catalog to refer to.

Buying a funky motor from a wrecker for $400 sounds like his retirement plan as whole bikes come for that, and sometimes run. That said, buying a parts bike is a very good idea; mine gets lighter all the time?..

And hang in there. GS twins are still my favourite ride and I've owned or ridden most everything. They're often referred to as 'starter bikes' but some experienced riders are quite happy to end up there too. Smooth, nimble, and you can run them hard without getting arrested.

 

[Andy24]

you can look on ebay i ordered for my gs400 '79 from japan for 32$

 

[Pod70]

I have used a company called CMSNL for parts. They are expensive but their website is great for finding part numbers. I think this may be what you are looking for
http://www.cmsnl.com/products/piston-setos05_1210344820050/#.VcDSQ_NVhHw

 

[Guest]

I have used a company called CMSNL for parts. They are expensive but their website is great for finding part numbers. I think this may be what you are looking for
http://www.cmsnl.com/products/piston-setos05_1210344820050/#.VcDSQ_NVhHw

If you read the blurb at the top of the GSX400 twin page on CMNSL they say the following: 'The engine worked fine as a 250, but in its 400 form was overstretched leading to poor reliability, making the model unpopular in Europe'. Also the term 'fast but fragile'.

Given that the same engine became the GS500 and earned a reputation as 'bulletproof', it's hard to see how this wasn't written by someone whose mind was 'overstretched'. The engine was never 'stretched' in the first place, but sleeved down to 250 to meet regulations for restricted hp and/or displacement bikes. I'll admit that going to four valves would allow you to rev to the moon, while the two valve motors hit about 9 and quit, but that's hardly a fault, and even then the motors were pretty tolerant. On the other hand there are Europeans who are in the habit of winding motors until they won't rev any more and then shifting. It can be cultural.

The reason they weren't popular was that the 250 was the learner model and the GSX400 four came out in '82 and [I think it's basically the Bandit motor] went faster and cooled better and all that. I'll agree that if you wanted to drive wide open from Amsterdam to Poland the four cylinder 400 was the better rig, but I have two of these engines with about 40K miles each and even the abused and ugly one is still in fine shape.

The two valve bucket and shim motors [GS450] should in theory suffer less cam wear, but the 4 valve motors I have are not showing any lobe wear. So quite where the 'poor reliability' shows up is a mystery to me. Plus I see lots of these motors still running around after thirty odd years so how does the 'poor reliability' fit into that?

 

[Sandy]

Although I've never dealt with them, here is the parts supply in the Netherlands:

classicsuzukiparts.nl

They even go by Suzuki part numbers. I think the number for standard piston rings is 12140-44110; they currently have ten sets in stock.

What you need is to download the factory manual and I'll see if I can find a parts catalog to refer to.

Buying a funky motor from a wrecker for $400 sounds like his retirement plan as whole bikes come for that, and sometimes run. That said, buying a parts bike is a very good idea; mine gets lighter all the time?..

And hang in there. GS twins are still my favourite ride and I've owned or ridden most everything. They're often referred to as 'starter bikes' but some experienced riders are quite happy to end up there too. Smooth, nimble, and you can run them hard without getting arrested.

I've dealt with them this year for the 750ES mid fairing pieces and his prices seemed very reasonable for what I wanted and shipping was fast. For these parts new ones were actually cheaper than used ones on ebay. It does pay to look around.

 

[Grimly]

If you read the blurb at the top of the GSX400 twin page on CMNSL they say the following: 'The engine worked fine as a 250, but in its 400 form was overstretched leading to poor reliability, making the model unpopular in Europe'. Also the term 'fast but fragile'.

Given that the same engine became the GS500 and earned a reputation as 'bulletproof', it's hard to see how this wasn't written by someone whose mind was 'overstretched'. The engine was never 'stretched' in the first place, but sleeved down to 250 to meet regulations for restricted hp and/or displacement bikes. I'll admit that going to four valves would allow you to rev to the moon, while the two valve motors hit about 9 and quit, but that's hardly a fault, and even then the motors were pretty tolerant. On the other hand there are Europeans who are in the habit of winding motors until they won't rev any more and then shifting. It can be cultural.

The reason they weren't popular was that the 250 was the learner model and the GSX400 four came out in '82 and [I think it's basically the Bandit motor] went faster and cooled better and all that. I'll agree that if you wanted to drive wide open from Amsterdam to Poland the four cylinder 400 was the better rig, but I have two of these engines with about 40K miles each and even the abused and ugly one is still in fine shape.

The two valve bucket and shim motors [GS450] should in theory suffer less cam wear, but the 4 valve motors I have are not showing any lobe wear. So quite where the 'poor reliability' shows up is a mystery to me. Plus I see lots of these motors still running around after thirty odd years so how does the 'poor reliability' fit into that?

I don't know where they got their opinion from but it's utterly rubbish. If anything the 400/4 version was the fragile one, several I knew of suffering from wrecked cranks. Otoh, it was a free-revving little jewel of an engine, and invited thrashers to thrash it all day. Unfortunately, it didn't have the bulletproofness of its predecessors and larger siblings.

 

[GregT]

The GSX400 twin is pretty much the same bottom end as the 2 valve 450 - and the later 2 valve 500. It's not fragile...
Where they do give trouble is the head. They crack from plug hole to exhaust valve seat inserts. I've had one come into the shop actually puffing smoke from the plug hole on one side - still ran reasonably well too. He rode it out too, after being told what was happening and that he should look for another head...

The 250 twin is very much a scaled down version. AFAIK, nothing is interchangeable between the 250 and bigger ones except the ignition.
The GSX400 four in the early air cooled version has lubrication problems...When they went water cooled, they fixed it.

I struck the finding rings and pistons problem with a 400 not long ago and went GSX750 Wiseco pistons. Thick base gasket needed but it's going very well.
Thread here somewhere "big bore gs(x) 400"
edit - the reason I went pistons and rings was because the ring grooves were badly worn. Before looking for rings, I'd check the ring side clearances to see if the pistons are reusable....

 

[Guest]

Greg T,

As yet, I haven't seen a cracked head on a 400X but then again I haven't seen the post mortems but just the bikes still running. How many have you seen? Is there a side story - valve adjustment, racing usage, etc.or is it just a random thing? IOW, is there anything one can do to avoid it?

I've seen a few abused and thrashed ones with done in top ends, but as yet no head cracks. So it might have been a batch defect that never ended up in Canada, or I just haven't seen it yet.

 

[GregT]

Greg T,

As yet, I haven't seen a cracked head on a 400X but then again I haven't seen the post mortems but just the bikes still running. How many have you seen? Is there a side story - valve adjustment, racing usage, etc.or is it just a random thing? IOW, is there anything one can do to avoid it?

I've seen a few abused and thrashed ones with done in top ends, but as yet no head cracks. So it might have been a batch defect that never ended up in Canada, or I just haven't seen it yet.

I've never seen one that hasn't cracked....And i've seen quite a few when i was in the trade and ran a workshop.The head appears to be the same thickness and layout as the 750/1100 but for some reason they're very prone to cracks in that area. The Honda CB250RS single is just the same - very hard to find a good head for either of them now.
What I can say is that i don't think we got many of the later versions such as the L. Once the 400 four was in production, very few of the twins made it here. Once Suzuki NZ saw the Impulse - GSX400X - water cooled four, and got offered a bulk price deal, the twins were dead here.

 

[Guest]

I've never seen one that hasn't cracked....And i've seen quite a few when i was in the trade and ran a workshop.The head appears to be the same thickness and layout as the 750/1100 but for some reason they're very prone to cracks in that area. The Honda CB250RS single is just the same - very hard to find a good head for either of them now.
What I can say is that i don't think we got many of the later versions such as the L. Once the 400 four was in production, very few of the twins made it here. Once Suzuki NZ saw the Impulse - GSX400X - water cooled four, and got offered a bulk price deal, the twins were dead here.

If you look at a two valve head, there's major finning next to the spark plug; the cam boxes are further apart and there's room. The four valve heads have nowhere near the finning. My guess is that the four cylinder version just goes faster for the same amount of throttle opening so you get more cooling that way.

Maybe we don't see the problem so much because people around here [Canada] don't consider a 400 as capable of going further than across town. It's a massive motor culture. There are lots of - or were before the air box and fender haters decided they were 'cafe' prospects - 400Ls abandoned with low mileage and weathered seats available for almost nothing, so spare engines were plentiful. But for every actual 'bobber' that I see on the road there must be a dozen or more ads for half chopped ones that just need 'finishing', for silly asking prices. As if you can take a $400 bike and hack the back end off with a torch and throw away the air box and fenders and it's worth 2 grand.

But maybe now they're being stored inside, and will be worth even less, being non functional. I like how the 4 valve head works, but if it only had two I'd be just as happy. We got the 400x twin from 80 to about 85 with just the E from 83 on. Considering that they didn't sell very well [not much did in that period] there are still lots on the road.

 

[Guest]

Curiosity got the better of me, so I set upon a 'resting' donor motor to see if it has cracks. It's got about 35k miles on it and hasn't had fastidious ownership by the look of it. I got it along with a seat and side panels I wanted; $100 whether I took the whole bike or not.

If you look at the heel of the exhaust cam you can see that it has been run with zero clearance at some point. The motor is in reasonable shape generally, but the head is cracked between the spark plug and the seat. Four cracks, one going halfway up the spark plug hole. Obviously it was still running anyway, but eventually?..

I have some thoughts on how to repair these, but will need to consult my aluminum welding guru and see what he says.

This being a piston ring thread, I'll leave it at that.

 

[GregT]

I've seen the repair done. All valve seats out, grind out the plug hole and cracked area. Weld it all up. Remachine for seats - and a 10mm plug rather than the larger oe size...Refit seats, recut seats...Swallow hard when given the bill...
The guy who did it here is a very good engineer but admitted afterwards it wasn't economic for his customer.

I see there were heads listed on that dealers list posted earlier...