How do I treat my bike from now on

[MarkT]

Ok first of all I gotta puncture and have to have a new tyre Monday which has peeded me off! When I started it I caught straight away roughly , always then have to then give it a bit of throttle until it goes up to 3k reduce the choke to 2k rev it again and the revs go back up to 3k (right in the misfire range!) and then reduce choke to 2k when it stays. Leave for a few mins while putting on my helmet etc but today when I straightened it up the revs just dropped to 1k?

I didn't know I had puncher at first but had to ride slow until I had to pull over and see what was up, but it was really misfiring at the slow speeds just sort of missing a few beats.

Now I'm really down as I have to work out how I'm going to look after it! The wet weather is certainly showing on it, but I don't know whether to treat it with tender care or do very basic work until it stops!

I really need it to last for 2yrs but now needs a lot of maintenance (valves oil filter carbs brakes etc) I have always got a thrill out of it for the last 6000 miles so def need a oil change at least! I do not believe the range of misfire has changed but I cannot work out why it does it.

A dealer has offered to do the valves for about £150 and then really needs a dyno to see what's up with the running which will cost .

How would you treat it , it is not brilliant nick looks wise and I never see me getting rid of it!

I have bent mr EC ears about it no end and I would like to check the valves but can you check them with the engine in the bike?

Would be interested in your thoughts !

[dobbslc]

Hi Mark you can bend my ear for a while as I'm off work with a bad knee for a few weeks!
You can check the valves with the engine in the frame ok and if they are all within tolerance then your sorted,
It is possible but a bit of a ball ache to swap the shims with the engine in if you have to.
Check the compression first and if that's ok then the valves probably aren't the cause of your misfire (allthough they might still need doing)
It's probably the carbs that need fine tuning but make sure they are cleaned first, ultrasonicly if possible as the tiny drillings in the carb bodies themselves can get blocked and you can't get them clear with just carb cleaner.
If you can get to a good dyno centre that can still deal with carbed bikes then it will be worthwhile. If you have a spare set that you know work perfectly you could try those.
If it's worse in the rain then check all the plug connectors, coils, plug leads etc including the pick up under the engine cover, take the cover off and check it's not sucking up water, this can happen when the engine is hot then cools down and the air inside contracts thus sucking in water. also have you swapped the pick up as it can play up more at low revs if it's a bit iffy. Check the plug leads for spark leakage in the dark as you will see and hear it jumping down to earth (engine case). RS sell a switch cleaner you can use on all the connectors it's called EML I think and it's brilliant stuff.
Stick with it if you like the bike. Trust me you won't find a better forum than this one for help & advice on any kind of bike.
Dobbs
Dobbs

[MarkT]

Thanks the misfire has always been there and I normally just ride round it but I'm on the 3rd set of carbs as good ones that have not been butchered are hard to get hold of. The misfire is always on the tinyest bit of throttle after that it goes great! But maybe not as fast as it should be but fast enough. I think that I have come to an agreement with the garage that if I check them and if they are out they will collect the bike and adjust. I do have quite a bit of spitting on the overrun so I think it is weak. Once past 3k it runs perfect which leads me to think a weak mixture.

If you know my bike you will be aware that it is a 1990 3tj with a genuine 1wg engine put in. That has had as many 3tj parts on it. It has 3tj carbs and exhaust headers. The exup ha been removed and it has a straight through exhaust which is very loud!
If you know what I have to do to be able to get the valve cover off I can get on and check them?

I have always loved the bike and all the 3tj engine parts were put on before I had the bike but took a lot of work to get it going to start with!

Thanks for reply and the other thing it fits me perfect.

I think the puncture made me really low and I suffer quite bad with the blues and starting to feel a bit more positive now thanks!!

I will feel happier when I done the valves , also the guys on here have been great!!

[dobbslc]

How is the engine mounted? as the older motors have no side mounts on the barrels like a 3TJ.
All of the 3TJ engines have 1WG stamped on them. If the frame mounts to the barrels it's a 3TJ engine.
I'm confused.

[Evilchicken0]

Firstly, it might be time to change the oil and filter, it sounds like it's a bit old.
The biggest problem is taking off the cam cover. You remember how easy it is to change the plugs ... well you'll be working in in the same wide open space. As that You might find it easier to take the rad (and mudgaurd) off to get some access. Once that's done the rest is just feeler gauges and moving the engine to TDC and BDC ....
To change the shims you have to lift the cams, it sounds difficult but isn't once you've done it

[Taggyd]

id check the coils. my race bike had the same fault and it turned out to be the coil. ive got a few spare shims from a 3en1 if you know what sizes u need if ive got em you can have em. got a whole 3en engine in bits. theres a chancethere might be a 3tj engine up for sale soon dep. on what happens with a guy wanting the rolling chassis.