Tachometer jumps around

[Jakeyz333]

Hey guys I just purchased the 5 cable set off eBay from Paul miller and replaced all of them except for the clutch cable. The tachometer bounces around 3500 at idle and doesn't seem to move much from there when gassed. What could cause this and how can I test to see if its the actual tachometer. Also do you have to open the trans cover to replace the clutch cable. Thanks Jacob

[GT750Battleship]

Hi,if you have replaced the tacho cable with a new one & it is still not working properly,I'd say you have a problem internally with the instrument itself ! There is a guy on the forum who repairs instruments if you want one repaired you need to contact "Waterbuffalo",
I'm not familiar with the T500 & the clutch set up..but yes if the cable goes inside that cover it will have to come off,unless it's like the GT750 with an outer cover,as I say I'm only familiar with the GT750! do you have a workshop manual,you can download from the Web for free !
Cheers,
Roger

[Vintageman]

Does the tach work when you are in gear running?

If you pull in the clutch lever the tach nor oil pump runs (don't run with clutch pulled in for too long).

I believe the clutch cable end is attached to engine top right rear rear behind carb where oil pump is. It screws into top of oil pump.

[Alan H]

Compare the lengths of the inners and outers between old and new cables. If there is a difference (a bit short or spacers/washers in one end), it won't work properly.

[Jakeyz333]

When I put it in gear it drops to 0 and as I let the clutch out it immediately jumped back to 3000. I think I forgot to mention it was doing this before the new cable as well

[Alan H]

When I put it in gear it drops to 0 and as I let the clutch out it immediately jumped back to 3000. I think I forgot to mention it was doing this before the new cable as well

Correct. Check Vintagemans' comment earlier in this thread.

[Jakeyz333]

I got that part I jus don't think idle is around 3000. What should idle be at out of curiosity

[parksie]

About 1400 to 1500 rpm

[Jakeyz333]

Well that tach still isn't accurate. I replaced trans oil last night with 20w50 castrol gtx. Is this the oil that is supposed to burn out your clutch? And to check the fluid level itself I know there is a Phillips screw on the rh side of the bike but even after I had drained all the fluid oil still crept out so I'm not really confident on the oil level what's a sure fire way to check it or should I remove the expelling screw until the fluid stops coming out?

[GT750Battleship]

Hi,bike on level ground..bike on centre stand...leave the screw out !
I check things with mine by measuring the amount I put in...then I know it's right !
unless the motor has been apart & it's bone dry !! I'm not sure about the GTX...but yes you do have to watch what you're using,some additives will give you clutch slip !
Cheers,
Roger

[Jakeyz333]

Thanks for the reply.. Do you know what additives do cause problems. And should I remove the screw now and let the excess drain out?

[parksie]

I personally wouldn't use Castrol GTX due to it having friction modifiers which can upset the clutch (Slipping) although some blokes on this forum do use it.
I prefer gearbox oil with a GL5 rating.

[Jakeyz333]

Okay thanks. On the oil level itself should I just remove the screw n let it drain until it stops or do I need to completely drain it.