31 replies to this topic

[paultdm850]

So back in July last year I bought a very low mileage 98 4tx to replace my tired old 99. After going through it over the winter and making it mint I hopped on the 98 for the first time a few weeks ago. To my surprise I found the 98 has a much noisier 3rd gear! Last night I took to the gearbox parts list for both years and found that Yamaha changed quite a lot of components in the gearbox, including 3rd gear(s), between 98 and 99, so this might explain why some have noisier boxes than others.

 

The gearbox on my 99 is pretty sweet compared to the other one. It's a pity it involves a complete engine strip to change the gears and shafts or I'd try and get the later parts and do it.

[dapleb]

Yeah. Have a later mk2 box to go in my next enjun fur this raisin.

[paultdm850]

Do you know if anyone has done a "walk through guide" on how to strip a gearbox? Sometimes people find clever ways to get around having to remove unnecessary stuff making it quicker and cheaper. 

[Studley Ramrod]

The only way to swap the gearbox is to split the engine casings in half, believe me I've looked for an easy way but there isn't one unfortunately.

[Got1now]

The only way to swap the gearbox is to split the engine casings in half, believe me I've looked for an easy way but there isn't one unfortunately.

How about a fettling session on this one Ian?

Might take more than an hour or so perhaps..........

Bet there'd be a few takers.

Meet up at yours shall we?

[Studley Ramrod]

Got my own to do so, errrr no.

[paultdm850]

The only way to swap the gearbox is to split the engine casings in half, believe me I've looked for an easy way but there isn't one unfortunately.

 

And that involves removing the barrels etc too?

Edited by paultdm850, 21 May 2017 - 03:40 pm.

[Studley Ramrod]

Yes, well it involves removing everything. Have a look at my mk2a bloggerydoodah for an idea.

[fixitsan]

Fit the low miles '98 pistons, barrels and head to the '99 bottom end ....

[drewpy]

mine whines in 3rd, good to know its normal even a little annoying

[Apache]

My 4TX3 has been perfect from new. My 4TX2 whines like a turbine in third only. Does no harm.

[drewpy]

who needs gear indicators when a whine will do

[paultdm850]

Just to update. I have done a few things that have improved 3rd gear noise a little. 

 

1/ 10W50 fully synthetic engine oil

2/ I applied 10mm self adhesive sound proofing foam to the top of the oil tank, to the underside of the fuel tank (Not above the air box) and to the inside of the little side panels under the front of the seat.

3/ I have Dynojetted the carbs (with the open pipe and pipercross filter that were already fitted)

 

Now, don't get me wrong, this has not done away with the noisy 3rd gear altogether. But I'm sure it's better. In fact, unless I'm imagining it, it seems to be getting better a little each time I ride it. I think the biggest improvement is the Dynojet kit. It makes the engine much smoother at low revs which seems to stop 3rd gear chattering quite so much on light throttle. And also, even though I run 17/42 gearing, it'll pull 4th gear at 30mph now, which it wouldn't do nicely before,meaning I spend less time in 3rd. The only down side is I'm down to about 45mpg, but I have more performance so...

 

I guess what I should add is, I have for the last decade or so worn ear plugs. And for this summer I bought my self a Sena intercom thingy, brilliant thing! I can listen to the radio from my phone with it as well as make calls and the like. But I don't always wear it, it depends on how far I'm going.

 

Also, my clutch is running the later stiffer Yamaha clutch springs and Wemoto steel (oil dimpled) clutch plates. I guess the thicker oil might make the clutch slip if it had the lighter clutch springs fitted.

[dablik]

I still wear earplugs with the Sena Paul and hear music really well, and i'm a bit hard of hearing

[paultdm850]

I still wear earplugs with the Sena Paul and hear music really well, and i'm a bit hard of hearing

Yeah, me too. Damaged the hearing in my left ear with a hammer drill a few years ago. If only I could turn back time....  

[dablik]

Yeah, me too. Damaged the hearing in my left ear with a hammer drill a few years ago. If only I could turn back time....  

 

I find putting your music through an equaliser as opposed to music app will give you a better sound quality as well, quality of recording will make a huge difference as well.......oops a but off the main topic sorry.

[MickC]

My 96 whines in 3rd dosent bother me in the slightest.

[drewpy]

mine used to whine in all gears till the missus stopped being pillion

[nunky]

hi all , 

 

reading the posts I'm not alone in having a whining 3rd gear , I have a 96 4tx with 32000on it  which i have had for a few years , 3rd gear has always whined but doesn't seen to be getting any worse , planning on a uk tour this year  and was thinking of a gearbox rebuild before i go  , is it worth the work or does the gear whine have no effect on the gearbox reliability.

any sound advise would be appreciated .

[fixitsan]

hi all , 

 

reading the posts I'm not alone in having a whining 3rd gear , I have a 96 4tx with 32000on it  which i have had for a few years , 3rd gear has always whined but doesn't seen to be getting any worse , planning on a uk tour this year  and was thinking of a gearbox rebuild before i go  , is it worth the work or does the gear whine have no effect on the gearbox reliability.

any sound advise would be appreciated .

 

If the oil runs clear and there's no metal particles on any trap magnets, then unless it sounds like an imminent disaster I would leave it.

 

Unless you're very keen

 

I did two rebuilds

My mk1 had a welded front sprocket because of spline failure, the welds failed on the way home from the MOT test, thankfully, after passing ! output shaft replacement needa f ull strip

My MK2 jumped out of I think 2nd or 3rd gears and I found a cheap secondhand gearset from a later model. Also a full strip down required

 

In either case it's a full strip, of everything. Well, you can leave the valves in the cylinder head. I'm not 100% certain about this but i think you could leave the pistons on the conrods connected to the crank, but the engine must be split and lots of things have to be removed.....and then a full gasket set which you'll need costs £70 - £100.

 

There's one or two bolts which go through the cases internally, if it wasn't for them life might be a little bit easier but it's a major job, and leads to other things such as replacing bearing shells, maybe rebuild the head ? Might as well do the cam chain. Inspect the oil pumps. .....

 

I rebuilt both of mine with a fair few new parts included, for around £200 each