Twincam.GTi

...And the part number is: 4G0 24161 0

Many thanks people, will try

On my XJ550 the left hand Petrol Tank badge (which is made of hard plastic) has stared to crack/fall to bits (so it now reads 'AMAHA ). So I go to my local Yamaha Dealer for a new one (who I have to say has been brilliant in the past and infact suprised me what is still available/been able to get for me despite bike being 25 year old) he checks part number and asks for £16.38 ($30.17) and told to wait a week ...this morning (after 2 days) I get a call, totally apologetic from parts chap saying item has been discontinued and a full refund of my money awaiting at dealership. So looks like i've got to have a search round the breakers/bone yards/ebay. Thus my question (at long last ) does anybody know what other models of Yamaha bike uses the same size of tank badge (to thus give me more choice/chance of finding one). Many thanks

I'm thinking of replacing the shock absorbers on '81 My XJ550 as the 'Hagon' shock absorbers that I fitted 14 year ago in 1991 are now locking very rusty. In fact the Hagon ones started to have the chrome peal off the springs after just to years of winter riding so this time I decided to look at alternatives. The ones I've looked at (remember I run to run this bike as a cheap 'Jalopy/hack/rat' ) are called SHOX and SHOKA which I think are the same firm/design. They are available in Black, Chrome or a Combination of Black & Chrome (which is simlar to my Hagon made ones) SHOX: SHOKIA: All advice greatly received Thanks.

I've never had to adjust the valves (or don't feel I need too ) on my '81 Yamaha XJ which is now at over 90,000mile and has never had any actual engine work ...yet Ooh lets see if I can reach that 100,000 mile barrier on the Original (untouched) Engine, Gearbox and clutch ...

drewpy Many thanks for that, all info is greatly received

Many thanks for picture, yes realised pistion is 'bonded' to diaphram (hasn't ripped, though, is fine, but just got concerned like anything when you disturb it for first time after a couple of decades). Oil change, yes did think about that, you're quite right. On a side note things done this year are: Replaced one of the igniter coils, which failed (second hand, came of 'Scrapper/Beaker' XJ550 , different size to original coil but does job!) Made own 'blade type' fuse box to replace well caroded (and breaking up) original fuse box I've fitted an 'O' ring chain for first time last month to bike (along with new sprockets), are these 'o'ring chains longer lasting? Replaced Tacho/rev counter cable (old one had stripped and leaking oil around seal where fits into engine). New sparkplugs (due to problem mentioned in first thread) An oil change Oh my I've spent over £90 ( $165 ) this year on bike thats more than i've spent in previous years (round where I live you can buy a 20 year old bike for that amount ) And i'm thinking of replacing the front mudguard again as the pattern one is getting rusty again (last replaced in '98) from everyday (including winter) use. Thanks once again to everyone for advice and help

I don’t need to take the head off (thankfully) . As stated earlier I thought internal damage had happened such as a burnt/chipped valve etc. because on number 3 cylinder petrol was going in but not igniting yet a sparkplug tester showed a superb spark on all four leads to the plugs, plus new plugs where fitted, the carburettors operated correctly (linkage etc.), so naturally you can understand my thought of some form of engine damage. So the rocker cover was removed and the engine just turned over to check that the cams operated the valves up and down etc. Then I thought even if valve was burnt it would still ‘fire up’ in the cylinder so rocker cover put back on and I decided to take the top off No3 Carburettor …and …believe it or not …but a good piece of fibre/cotton/cardboard was in the carburettor tube, stopping all movement of the carb piston, hence ‘neat petrol’ going into the cylinder and flooding everything. It would appear the air filter element has broken up and a few bits of its fibre went in the carb. The bike appears to be running fine now (famous last words ) but for a short while did smoke a bit due to all the unburnt fuel that has gone down the exhaust. So my question to you all this time is …can anyone scan me an exploded diagram/picture of the carburettors (sorry to pester again ). Although every thing is running fine I’m just a little concerned about the carb (rubber diaphragm at the top cause I’ve disturbed it for first time in 24 years etc.) . Plus can anyone think of any damage that might have been cause by this? Thanks again for help.

I don’t need to take the head off (thankfully). As stated earlier I though internal damage had happen such as a burnt/chipped valve etc. because on number 3 cylinder petrol was going in but not igniting yet a sparkplug tester showed a superb spark on all four leads to the plugs, plus new plugs where fitted, the carburettors operated correctly (linkage etc.) So naturally you can understand my thought of some form of engine damage. So the rocker cover was removed and the engine just turned over to check that the cams operated the valves up and down etc. Then I thought even if valve was burnt it would still ‘fire up’ in the cylinder so rocker cover put back on and I decided to take the top off No3 Carburettor …and …believe it or not …but a good piece of fibre/cotton/cardboard was in the carburettor tube, stopping all movement of the carb piston, hence ‘neat petrol’ going into the cylinder and flooding everything. It would appear the air filter element has broken up and a few bits of its fibre went in the carb. The bike appears to be running fine now (famous last words) but for a short while did smoke a bit due to all the unburnt fuel that has gone down the exhaust. So my question to you all this time is …can anyone scan me an exploded diagram/picture of the carburettors. Although every thing is running fine I’m just a little concerned about the carb (rubber diaphragm at the top cause I’ve disturbed it for first time in 24 years etc.). Plus can anyone think of any damage that might have been cause by this?

very nice. With regards to my colour scheme, whats painted white on yours is black on mine and whats red on yours is orange on mine. What exhaust is that, i'm running aftermarket 4to1 Motad (good quality chrome on 'em) Thanks for your offer to 'dig out' info, will probabley pester you for more info in the future, hope you don't mind . Take care

Hello everybody, In my family we run a 1981 Yamaha XJ550 (black with the orange pin striping)which we have owned since 1989 and used since as everyday transport all year round (winter and summer). It has now reached roughly 90,000 miles without an engine rebuild as yet (but read more of later) and still on original clutch/drivetrain. Naturally during our time of ownership it has had a few replacement exhausts (thanks to all that lovely corrosive salt they put on the roads in the winter in the UK ), we've had to do a partial re-wire (original fuse box etc. carroded to bits), many tyres, many fork seals and many chain and sprocket kits plus many, many regular oil and filter changes. The panels/frame are still the original ones except the front mudguard which we replaced in '98 due to the original rusting (lovely UK Climate again). Only mods/Extras on bike are a JMC back suspension and engine protector bars. Not a minter but a well used and reliable mode of transport. However this week we suspect we have a burnt valve . So a top end strip down may be required, my mechanical apptitude is fine due to years of running old timers/Jalopies/bangers of various sorts but I will be asking little bits of info, so firstly here goes Does anybody here have the torque settings and tightening sequence for the cylinder head (Yes I know I should get a workshop manual ...and will be ...how I've managed till now I do sometimes wounder ). Many thanks and happy riding.

For 1981 Yamaha XJ550. Does anybody here have the touque settings and tightening sequence for the cylinder head (Yes I know I should get a workshop manual ...and will be ...how I've managed till now I do sometimes wounder ). Many thanks and happy riding.

Hello everybody, In my family we run a 1981 Yamaha XJ550 (black with the orange pin striping)which we have owned since 1989 and used since as everyday transport all year round (winter and summer). It has now reached roughly 90,000 miles without an engine rebuild as yet (but read more of later) and still on original clutch/drivetrain. Naturally during our time of ownership it has had a few replacement exhausts (thanks to all that lovely corrosive salt they put on the roads in the winter in the UK ), we've had to do a partial re-wire (original fuse box etc. carroded to bits), many tyres, many fork seals and many chain and sprocket kits plus many, many regular oil and filter changes. The panels/frame are still the original ones except the front mudguard which we replaced in '98 due to the original rusting (lovely UK Climate again). Only mods/Extras on bike are a JMC back suspension and engine protector bars. Not a minter but a well used and reliable mode of transport. However this week we suspect we have a burnt valve . So a top end strip down may be required, my mechanical apptitude is fine due to years of running old timers/Jalopies/bangers of various sorts but I will be asking little bits of info, so firstly here goes Does anybody here have the touque settings and tightening sequence for the cylinder head (Yes I know I should get a workshop manual ...and will be ...how I've managed till now I do sometimes wounder ). Many thanks and happy riding.