Restoring my bike, but what about the engine?

[Anonymous]

I have a 1981 GSX400E 8V that I am planning to restore during the summer. My plan is to rip it apart and sandblast everything and then paint it. How expensive is it to get those chromed screws and chromed stuff re-chromed?.

The bike has 69.000kms on the clocks, is it time go give the motor alittle "restoring" also?. I think the cylinder base gasket is leaking, so I was planning to take off the cylinder, get them honed and replace the piston rings, would that be a good idea?. Also inspect the cam chain, the previous owner said that the chain had been changed one time, but I do not know the milage the engine had when this was done. How long does these chains last?.

I have wrenched pretty much in my life, though I`m only 18 years old.
I have a Haynes manual for my bike and my dad is also an experienced mechanic, so don`t you think that we should manage to do the job?.

The engine is running pretty nice now, but it has a tendency to get hard to start as soon as the temperature drops below 10 C degrees. It doesn`t smoke alot or anything like that. I can here some (what I think) is valve noices.. but many guys sais that it`s normal, or ?

Hope someone can give me som advises on what do do with my GS engine, or if it is necessary.. ?

 

[Anonymous]

Be careful about the rings. There are some sizes for our bike that are no longer available. The same goes with pistons, I think it's either the stock size or one size over bore that is not around anymore but I do not remember. www.motofiches.com has a schematic of our bike online. Just check your frame code to make sure you're looking at the right bike. You'll be able to figure out which of the parts match up with the GS1100s and 1150s. So far I know that the cam chain tensioner parts, much of the valve train, and other stuff is the same.

The nuts and bolts are still available from Suzuki and cost about a dollar or two each, there aren't really a whole lot of them on the bike so it shouldn't cost a much to buy new ones. You'll also have the old ones
around in case the new ones break or fall out on a rough road.

I'll post some miscelaneous info below, but my bike is one year newer than yours so some parts are different. I know for sure that the rear sprocket is. I've got a microfiche for my bike (and probably yours) in the mail so in a few weeks I'll be able to give you part numbers if you can't figure out the French website I gave you.

Good luck, Steve

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JS1GK53A8C2100361
G3414-15357-10923
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Microfiche for Canadian GS400EZ 9900M-61133
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Below were taken from Suzuki?s own GSX400E/L/S Service manual.
Float height 22.4 +-1.0 (Fuel level 5.0 +-0.5)
Main Jet #117.5 Main Air Jet 0.6 Jet needle 5D69-4
Pilot Jet #42.5 Bypass 0.9,0.8,0.8 Pilot Outlet 0.8
Valve Seat 2.0 Starter Jet #32.5
Pilot Screw 1 1/2 turns Pilot Air Jet #125
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Haynes Manual ? GS/GSX 250, 400, 450 Twins
ISBN: 1 85010 253 8
UPC: 0 28245 00736 1

Clymer manual only covers shim and bucket 4 valve engines, not tappet 8 valve engines
ISBN: 0-89287-237-3
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Below were taken from a universal parts guide
3x18 front tire, 3.00 Dunlop Gold Seal F11 will fit, 3.5 Dual Sport Cheng Shin will fit
3.5x18 rear tire, 110/90 Dunlop K591 will fit, 4.1 Dual Sport Cheng Shin will fit
Spark plugs, DR8ESL, 0.6 to 0.7 mm
Valve clearance of 0.008 to 0.013 mm
Fork oil 178 ml
Carb float height 22.4 mm
110 links of 530 chain
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1 ?? chain slack??, 1 ?? seems to work well as the chain relaxes to this spec on its own
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http://www.partspartners.com/html/gsx400.html for specs below
Timing may be 20 degrees at 1650RPM to 40 degrees at 3500RPM
Valve clearance of 0.008 to 0.012 mm
Fork oil in CC (ml) 191/169, different than above
Resistance of pulse/points coil is 60 ? 80 ohms
Primary coil resistance is 3 ? 5 ohms, secondary is 20 ? 30,000 ohms
175 pounds dry
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Below are actual #s read from parts on my 1982 GS400EZ
?Replaced with? means I put those parts on my bike instead of OEM parts; it does not mean that Suzuki has changed the OEM parts specifications.

Count Origin Specs
1 JAPAN Sprocket hub seal, 30.5 52 8 2, Circle around N
- Replaced with Chicago Rawhide 11639
-CR 30 52 8 HMSA7 R, inner diameter is smaller by 0.5 mm
1 JAPAN, NACHI Sprocket hub ball bearing, sides are not sealed, 6205
- Replaced with SKF 6205-2RS1/C3, rubber seals on both sides
2 JAPAN, NACHI Swing arm needle bearings, TA2230Z G6
- Replaced with NACHI-FUJIKOSHI CORP. TA2230
1 JAPAN, KOYO Rear wheel ball bearing, metal shield on outer side, 6303۰Z
- Replaced with SKF 6303-2Z, shields on both sides
1 JAPAN, NTN Rear wheel ball bearing, metal shield on outer side, 6203Z
- Replaced with SKF 6203-2Z/C3, shields on both sides
2 , NOK Double lipped fork seals,
XXXXXX 15 BR2651IE XXXXXX 33-00
2 , SHOWA 4440 rear shocks, ~13? long centre to centre
1 , Fram Oil Filter, CH6000
1 UK, EBC Front brake pads, FA51, AF16GG
- High performance organic series (FA), Lead/Asbestos + Nickel Free
- Removed Tokico JB CXFF
1 , NOK Starter input seal, AG0585E 8, centre looks like an o-ring
2 JAPAN, NACHI Front wheel bearings, rubber seals on both sides, 6302NS
1 USA, Motomaster Battery, YB10L-A2, M2210Y, R208LX
-9 cm front to back x 14.5 cm Wide including 1 cm vent x 15 cm Tall
1 Sprocket cover bolt, screw head
-replaced with M4 x 60 mm hex head
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Fork seals are 33x46x11 according to Cycle Salvage (found to be correct)
Fork seals, closest size available, are 32x46x8 according to General Bearing Service
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Stock Part Numbers
Air Filter: 13781-44500
Front Sprocket: 27511-44000 16 tooth, 006426 from Sprocket Specialists
Rear Sprocket: 64511-44000 45 tooth, 006189 through Kimpex
Cam Tension O-Ring: 09280-06005 One large, one small
Cam Tension O-Ring: 09280-21013 Which one is which? 
Cam Tension Seal: 09284-10006 10x16x4
Cam Tension Gasket: 12837-47010
Oil Plug: 09247-14001 21 mm socket
Oil Plug Washer: 09168-14004 Shows as spark plug gasket on receipt?
Oil Filter O-Ring: 16518-45000
Oil Filter: 16510-45040
Swing-arm Bushing: 61251-45001
Countersunk Screw: 09127-05015 Cam end caps, clutch tensioner cover
Igniter: 32900-44410
Starter: 31100-44110 Nippondenso 028000-6501 12V 9U 29
Starter O-Ring: 09280-24003
Clutch Cable: 58200-44100 46.5? of cable including ends
Valve Cover Gasket: 11173-44204
Cam Breather Gasket: 11177-45400-H17
Brake Lever: 57420-49101
Clutch Lever: 57620-49111
Exhaust Port Gasket: 14181-01D00
Speedometer Cable: 34910-44400 Comes Greased
Throttle Cable: 58300-00A00
Left hand mirror perch and clutch lever:
57500-49131
Caliper Bleeder: 43085-001 Kawasaki Part, Threads ~3 mm shorter than stock, black with green tint, larger 10 mm nut, rubber cap included

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?? PVC electrical conduit fits inside of the fork tubes. It is cheaper to buy a 90? radius elbow and cut the spacers off of it rather than buying a 6? pipe.
12 mm washers fit into the fork tubes. 4 mm fender washers do not fit.
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A flat washer, (.035-.040) should get you close to the equivalent of one notch on an adjustable needle.
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Starter Brush Info:
New starter brushes are 8.75 mm x 5.75 mm x 11.80 mm
(roughly 12 ? 13 mm in Factory GS1000 manual)

Suzuki says the minimum is 8.75 mm x 5.75 mm x 9 mm (Factory GS1100EX manual)

I found that a worn positive brush is about 8.75 mm x 5.75 mm x 7.45 mm on my GS400EZ at about 40,000 km and 22 years
-at this point arcing will dirty up commutator causing no-start or slow start

My negative brush was in much better shape at 8.75 mm x 5.75 mm x 9.85 mm as they tend to last longer

Some positive brushes come connected to a bolt with a rectangular head and long grip length, the GS400EZs starter requires a bolt with a square head

 

[Anonymous]

Thanks Srivett! Alot of useful information there!

But do you think I really have to change the pistonrings? I bet they arent that expensive and isn`t it smart to replace them when you have the cylinders off? since you don`t have them off the often..

Anyway, here are some pics of my bike. The first ones are of the bike when I first got it (all pics where it`s red

Compare this pic with the "after" pic below

A little history on the bike.
I traded my boat for the bike, the bike had been laid down into a ditch, so the front fender was smashed, broken levers, some scrathces here and there. The bike didn`t seem to be very vell taken care of, so I decided it needed some "care" . I was only 16 years old when I got it, I`m 18 now.
I took off the tank, side panels, rear part and the "stripes" under the seat, sanded them and then painted them, with spraycan though but the result was very good, after failing with spraycans on different projects several times. I got a new universal front fender, had to drill the mounting holes in it, I was very nervous that I wouldn`t get them right, but the were right. I replaced both levers, the battery, sparkplugs, engine oil, installed K&N cone filters, replaced some bulbs, and some stuff that I probably don`t rembemer right now. The main problem with the bike was that the ATU unit had broken off when the bike was laid down into that ditch, it hit a pipe. (the screw that held the ATU unit had broken off into the hole, and the previous owner had started drilling it out, and messed the hole up badly. We drilled a hole with diameter 13mm (or something), then we pushed a little iron piece into it, which we had made a hole in and threaded with 6mm threads, we couldnt install a bigger screw since it had to go through the ATU unit and I didnt want to bore in the ATU unit.

We fixed the ATU unit, and the bike fired right up, and have been running nicely after that.

Here are the after pics:

I also went over several parts and removed surface rust and painted them with a brush (screws etc). I also polished everything that was polish-able

Also the instruments was refreshed, compare this pic with the before pic above and see the difference.

It`s been about 1,5 years since I "refreshed" the bike, but now I want to really make it like new. I love that old bike, she`s my baby.

 

[Anonymous]

Come on you guys ! Give me some replies

 

[Bert Patterson]

I've got zip for technical skills, but that's a beautiful looking ride. Never seen one.

 

[Anonymous]

Well, if you resurface the cylinders you need new rings regardless of their condition. Otherwise you just need to measure everything. I checked into the rings and it's the 050 over size that is no longer available. The GS1100 pistons have very similar part numbers so maybe you can get a set of them and put them in for an overbore! There's lot of them available from racers who blow a motor and end up with 2 or 3 good pistons.

Steve

 

[Anonymous]

You mentioned that the bike runs fairly well except when the temp gets a little cooler. You also mentioned that you installed pod filters which is going to make it run lean and when it gets colder outside, it will run leaner still so that might account for the reason it's hard to start when it's cold out. You may want to back the a/f screws out a 1/2 turn and raise the needles a little to see if that helps.

Have you done a compression test on it yet? If the compression is good, I would leave the engine alone and rebuild when it needs it. If the compression is low, try putting some oil down the cyls. and if it goes up, it's most likely the rings, if it doesn't make a difference it could be the valves. I would adjust the valves and sync the carbs and see if that improves things.