1981 GS250 Rebuild Project

[philo]

I have been asking random question and getting a lot of great help for about a year. Lately, though, the bike has become more of a rebuild so I finally am getting around to creating a thread for it. Just wanted to say thanks again to everyone who helped me on my other posts.

About the bike: 1981 GS250 with around 5,000 miles (so it said). No maintenance history. All stock parts. Good condition really but lots of work to be done. I purchased it last year and have been riding it the entire time but recently I have really started to get things done. Here is what has been done so far:

Full carb rebuild (full strip/dip, new seals/washers)
New intake/airbox boots/seals/clamps
New air filter element with weather-stripped airbox
Full fork rebuild (including ALL washers [thanks for the AMAZING post with home-made tool])
New swing arm bearings (Auto-zone tool rental has a slide hammer and bearing puller attachment that makes removal super easy...i'll find a link to it and post it for others near Auto-Zone...pulling them out was so easy it was actually fun)
New drive train (f/r sprockets and chain)
Progressive 12 Series rear shocks and springs
PitReplica seat cover (free because it was used for their template)
New tires
Electrosport stator/RR (RR was dead, stator was low on output but still working so I decided to replace both) single point ground and direct frame/neg connections; stator wired direct to rr, rr to pos bat with inline fuse; again AMAZING posts/articles/guides, thanks!! Plan to re-do all the connections soon)
New clutch springs (original plates but no slip)
New rear brake springs for pedal and shoes
New cables
TONS of new seals/gaskets/springs...if I came across one I replaced it.
New mufflers (from a Harley; free....again great advice from the forums. Nothing available for a GS250 so fabrication was a must and you cannot beat free! Old mufflers had large holes. New intake seals and fully sealed the mufflers)
New plastics
New spark plugs and caps...original coils

Where I am now: Waiting for oil pump gaskets. I broke the oil pump sprocket and decided to replace the o-rings while I was down there. Also ordered a new lock washer for the clutch. I ordered a hel ss brake line but after reading about brake rebuilds I am waiting so I can do a full rebuild on the mc and caliper. I also ordered new caps for the crankcase (I spent a lot of time sanding it while watching my political shows and replaced with hex bolts). Not sure what I will do next but eventually I will paint it once it runs well. I bought a carb sync tool on cl for $50 with the attachments so sync'ing the carbs will be high on the list, and another valve adjustment, before it hits the road.

I had one question also: My fuel petcock seems to work great. I have read a lot about the failures of rebuilding them and the recommendation to replace it before it fails. BUT I read about it after I ordered new seals for it and I don't really have the cash for a new one. So should I just leave it alone until I can buy a new petcock or can it not hurt to replace the seals? It sounded like the rebuild process was assuming some kind of damage other than just leaky seals but I was a little confused. Sorry if I am asking something answered; the petcock topic is loaded and I read a lot without finding anything.

Thank again to everyone that has helped! I will get a picture posted soon. If anyone has suggestions on what else I should do to make the bike run well I would really appreciate it.

 

[Guest]

Hey Philo! Nice to see another twin rebuild I can follow along on

You're missing one key ingredient though... pic's! We gotta see the beast!

Not sure I can help out on the fuel tap situation though as I didn't even try to rebuild mine, I just bit the bullet and bought a new one as it was less than $US80 from Boulevard Suzuki...

 

[hjacobmiller]

Sounds like you've been doing some great work!

I don't know if this will work, but here is what I sprung for on my GS300:

http://www.amazon.com/Supply-Fuel-P...&sr=8-1-fkmr1&keywords=suzuki+gs250+fuel+cock

I know the engines are the same, but I don't know what your fuel tap is like for the 250.

You may already know this, but from what I've encountered the 250, 300 and 400 share a lot of parts.

Good to see another twin!

 

[razor02097]

welcome to the forum

Looks like you have a pretty good ambitious plan. Make sure you break it up into smaller projects so you don't become discouraged. We would love to see your bike so when you get some pictures please share!

Also join our group! Small Engine Big Ambition

 

[philo]

Thanks for the replies! Great advice breaking things into smaller groups. Unfortunately I usually had 2 or 3 going at once due to my impatience and lack of experience...but I am learning at least.

Currently I replaced the handlebars and dyed all the plastic back to a nice black color. I did this while waiting for the seals for the oil pump to arrive thinking it would be an easy swap...it wasn't. I put everything back together yesterday and the engine would not start/turn (or even make a noise). All the lights are working correctly so I am thinking it must be either the connection at the clutch (a safety mechanism where you have to pull the clutch to start the bike) or the start button. I do not think it could be related to the oil pump/clutch that I also put back in, but mixing projects makes it hard for someone who knows as little as I do. I aligned the gears for the oil pump and everything looked straight. All the gear teeth looked good and the clutch went in without much trouble. It is shifting gears fine froom what I can tell with the engine off.

Does this sound like the approach I should be taking, checking the start button and safety clutch mechanism? Would it be worth push starting the bike to see if it runs?

Here are a few pics...I'll post more complete photos once I finish.

 

[Guest]

If the issue is the clutch switch, then push starting it won't work either.

Have you turned the motor over by hand via the 19mm nut under the timing cover? That will tell you if the clutch or oil pump is seizing it up.

There might be a side stand switch as well, some models have those too.

Personally I'd just bypass both the above as they seem to be the culprit for non-starting on many occasions.

She's looking very neat though

 

[philo]

I disabled the safety mechanism at the head-light and the bike started right up. Unfortunately it was leaking oil from the clutch push rod seal. When I initially started focusing on restoring the bike it was due to having the chain fall off and bending the clutch push rod. I tried to bend it straight and buy a new seal but apparently not straight enough. So I am essentially back where I started...

Can I bring it to a machinist and have it straightened, or does anyone have a clutch push rod for a GS250 for sale, or does anyone know of any after-markets available? I saw some on eBay but they do not look like my clutch push rod. They all look like metal plain cylinders; mine has a strange bit looking end on one side. Any help would be greatly appreciated. Thanks.

 

[Guest]

I disabled the safety mechanism at the head-light and the bike started right up. Unfortunately it was leaking oil from the clutch push rod seal. When I initially started focusing on restoring the bike it was due to having the chain fall off and bending the clutch push rod. I tried to bend it straight and buy a new seal but apparently not straight enough. So I am essentially back where I started...

Can I bring it to a machinist and have it straightened, or does anyone have a clutch push rod for a GS250 for sale, or does anyone know of any after-markets available? I saw some on eBay but they do not look like my clutch push rod. They all look like metal plain cylinders; mine has a strange bit looking end on one side. Any help would be greatly appreciated. Thanks.

Mate you're in luck! Your clutch pushrod is shared with the following models:

1980 SUZUKI GS250T
1980 SUZUKI GS450ET
1980 SUZUKI GS450LT
1980 SUZUKI GS450ST
1981 SUZUKI GS250TX
1981 SUZUKI GS450EX
1981 SUZUKI GS450LX
1981 SUZUKI GS450SX
1981 SUZUKI GS450TX
1981 SUZUKI GS550LX
1981 SUZUKI GS550TX
1982 SUZUKI GS450EZ
1982 SUZUKI GS450LZ
1982 SUZUKI GS450TXZ
1982 SUZUKI GS450TZ
1982 SUZUKI GS550LZ
1982 SUZUKI GS550MZ

What this means is if you look at this fiche from Boulevard Suzuki:

http://www.boulevardsuzuki.com/fich...y=Motorcycles&make=SUZUKI&year=1980&fveh=2093

You can not only replace it as a genuine new item but you can use the upgraded two part version used on the later models like mine, so if you bend it again you can replace the bent part without removing the clutch!

Parts 20 and 21 are what you need, total of $17.66 from Boulevard...

 

[philo]

Awesome, thank you so much!! =)

Both parts are ordered along with a new oil seal and plate. I will post again once it arrives and I am FINALLY riding! I ordered from BikeBandit for speed (I am in California).

The front brake is a little spongy but aside from a rebuild of the mc and caliper I am about done with mechanical work until I tackle the engine top-end for a rebuild, but thats far off unless the comp test comes out low. Next I am looking towards mirrors and blinkers (I am not fond of how far they stick up and out, respectively), and those emgo mufflers to replace the harley mufflers I am using. They looked great on the gs300 that posted the link.

Anyways thanks again, this forum is amazing.

 

[Guest]

No problems mate, but good luck with Bike Bandit! I've seen a few issues reported with them on here where they take forever to ship etc. but hopefully they're just odd ones and your order will be fine...

If your brake is spongy, have you replaced the rubber hose yet? If that thing's 30 years old then it could be a major issue sooner rather than later.

I put a braided steel line on mine with the stock (rebuilt) caliper and a new M/C and the difference is incredible. Forgotten the name of the company now but it was cheaper buying it on eBay from Canada including shipping than buying it locally here.

And yeah, this is a great forum

 

[hjacobmiller]

Nice!

Really clean too!

Good to see progress.

 

[philo]

The clutch push rod arrived today. It looks different than my old push rod. Is this the correct replacement piece? It does not have the strange twisty bit type end. Does it install any different than the old push rod other than being two pieces? It seems to be slightly too large to slide into place; the end caps catch something if you try to slide it through. Here is a photo of the old and new 2 piece push rod. Thanks for the help.

 

[Guest]

Looking again at the parts fiche I can't see that twisty bit identified, but they're not the most detailed drawings either.

However, the part numbers definitely indicate the new two piece rod should be an upgraded replacement.

The longer piece with the flat ends should slide in from the right before the clutch goes in, and the left should slide in from the left.

I think the idea was that if you bent the push rod due to the chain breaking or whatever that you could replace the end without having to remove the clutch...

Edit: Just had a thought... is your 1981 year coming from the manufacturing date on the compliance plate? If so, what month? If it's late in the year, it could be an '82 model, and the parts fiche shows a completely different part number and rod for that...

 

[Woodsy]

Gotta love the 250, same engine that was in my first bike, nice looking bike too

 

[philo]

The year is coming from the pink slip, which reads 1981. I do not think I have ever seen a compliance plate on my bike but I do not believe they made an '82 GS250, or at least I was told they went to the 300 in '82 and stopped the 250 in '81 (but it is just hearsay and could easily be wrong). I also checked the 450 service manual and they had a nice detailed photograph of the pushrod and it looked identical to mine, including the twisty bit end. The replacement pushrod seems like it would fit perfectly if it only had one of the two small cap type pieces on it. The rods themself are the same size diameter but the cap is slightly larger. Could it be the case that the pushrod sleeve (for lack of a better word) gets narrow on the 250 models and not other models like the 450? Or could I just need to push harder for a snug fit? It looks so very close to fitting, but the narrowing is ever so slightly to small. I am at a total loss here (which is not unusual I am trying to hold back from grabbing some light sand paper and sanding one of the end caps on the larger pushrod piece until it is small enough to slide through...after a month of sitting I am excited to get her back on the road but I really don't want to make any more careless mistakes from lack of patience & understanding. Thanks for all the help.

 

[Guest]

The year is coming from the pink slip, which reads 1981. I do not think I have ever seen a compliance plate on my bike but I do not believe they made an '82 GS250, or at least I was told they went to the 300 in '82 and stopped the 250 in '81 (but it is just hearsay and could easily be wrong). I also checked the 450 service manual and they had a nice detailed photograph of the pushrod and it looked identical to mine, including the twisty bit end. The replacement pushrod seems like it would fit perfectly if it only had one of the two small cap type pieces on it. The rods themself are the same size diameter but the cap is slightly larger. Could it be the case that the pushrod sleeve (for lack of a better word) gets narrow on the 250 models and not other models like the 450? Or could I just need to push harder for a snug fit? It looks so very close to fitting, but the narrowing is ever so slightly to small. I am at a total loss here (which is not unusual I am trying to hold back from grabbing some light sand paper and sanding one of the end caps on the larger pushrod piece until it is small enough to slide through...after a month of sitting I am excited to get her back on the road but I really don't want to make any more careless mistakes from lack of patience & understanding. Thanks for all the help.

Mate, my apologies, just looked again and I must've been seeing things last night... I was looking at the GN250 in '82, and you're right that there is no GS250...

In that case, the part numbers still stand correct and yes it should fit.

It may be that they don't list it as a direct replacement for the 250's because of what you're saying.

If you put them side by side, does the new 2 piece match the old 1 piece exactly for length? If so, and the only difference is the width of the flat piece, I'd get that sandpaper and go for it...

 

[philo]

Sanding failed, the metal was very hard and the cap ended up poping off effectively shortening the pushrod by a half inch. I looked online and noticed that the GS300 from '82 uses a slightly different (longer of the two pieces) pushrod. But it also was not listed as an alternative on the parts fiche; it did look a little smaller on one of the ends so it may very well work but I had a different idea.

It seemed to me that if I were to cut my original OEM pushrod to the length of the longer of the two pieces from the new pushrod, and used the smaller of the two pieces from the new push rod, that I would essentiall have the same thing. Some sawing and sanding later and I had forged my original into a smaller two piece. Bottom-line is that it seems to have worked great, the bike is riding again and seems to be sealed tight without any oil leaks. The ride is amazing compared to what it was before, just need to save some $$$ for the spongy front brake rebuild.

Still have to check the valves again and sync the carbs, and eventually tackle the cam tensioner because I have the seals to rebuild it already, but after a month of sitting the cam chain tensioner rebuild will have to wait. I will post some photos of the bike fully back together shortly. Thanks again for all the help, especially Pete for helping me get through this intimidating fix.

 

[philo]

 

[Guest]

Mate well done! A bit of ingenuity never goes astray with these old beasts

She's lookin' real neat and tidy now, a very nice example of a 250 there :clap:

 

[7981GS]

She looks stunning!

Eric