Engine holding revs

chronyx · Post by **chronyx** » 05 Nov 2007, 21:15

My 1989 mk1 seems to hold onto engine revs from 1st to 2nd gear changes.

You can feel the gearbox struggling to engage second through the level, as it clatters.

I think it could be clutch drag stopping the engine spinning down as I felt some engine braking with the clutch pulled in.

It has 10w40 oil in the gearbox, could this cause it?

Any other ideas?

Thank you

slider · Post by **slider** » 06 Nov 2007, 05:46

its supposed to have 10/30 in it really,but i doubt that'll cause it.is the clutch lever tough to operate?.mine was but i didnt think any thing of it until i replaced the cable and the lever operation went smooth and lighter.also the clutch basket forks can get stepped from years of use,they can be filed smooth
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*reproduced from knackereds project*

http://i183.photobucket.com/albums/x212 ... Basket.jpg

Second hand clutch basket turned out to be as worn as original. Only option was to file down teeth. Very fine file first followed by 1200 wet and dry stretched over file.

I've tried to take as little as possible off. We will see how it works?!

http://i183.photobucket.com/albums/x212 ... Basket.jpg
**************************************************************************************************************************
you could try that and fit new plates and springs while its stripped that far

oneandonly04 · Post by **oneandonly04** » 06 Nov 2007, 07:49

i have a good AR clutch plate and basket set...

chronyx · Post by **chronyx** » 06 Nov 2007, 08:16

Thanks guys

The lever is nice and light and smooth, if the engine revs dropped quicker it feels like it would shift sweetly.

Sprayed some carb cleaner in the pilot adjuster to see if there was crud but it hasn't really made any difference.

Post by **knackeredMk1** » 06 Nov 2007, 09:01

It's very likely that your throttle cables are just sticking a bit. This is usually a sign that they are on the way out so I would get them checked. If you don't find any frayed ends or kinked inners then give them a good oil through a cable oiler.

chronyx · Post by **chronyx** » 06 Nov 2007, 16:52

Nope they're free as anything!

I guess it must be something clutch related as I struggled to push it down my sloped driveway this lunchtime with the engine off, in first and the clutch lever in.

I always though a knackered clutch slipped though?!

Post by **scrubs** » 06 Nov 2007, 17:10

Does the bike creep forward when it's running in first with clutch engaged?
can it find neutral easy when its running?

either way..
crappy/too hevy oil can cause clutch drag so I would drain and fit some
decent, lighter, sythetic oil first before trying anything.

If you have no luck, your probably gonna have to
inspect the plates and basket. knackered clutches can drag too specially
if the spigot bearings shot.

but saying all that if the revs are holding on its gonna be harder
to engage the clutch and I wouldent relate the rev problem to the clutch..
hmmm..

try the oil change first and see where you stand.

chronyx · Post by **chronyx** » 06 Nov 2007, 18:00

Hi scrubs, yes you can feel it pulling in first with clutch in.

Neutral can be a pain to engage but it's not mega bad.

I'll get hold of some good oil and give that a go.

Interesting that knackered clutches can drag too, didn't know that!

So, the way I understand it, if it's dragging then the road speed is still getting transmitted to the gearbox/engine with the clutch pulled in making gear changes harder - imagine changing gear on the over-run!

Thanks.

Post by **scrubs** » 06 Nov 2007, 18:19

yeah theres a few things that can cause the drag
like warped clutch plates, overly tight springs, old oil
or the one my moneys on - oil thats too heavy, which
causes the plates to stick.

chronyx · Post by **chronyx** » 06 Nov 2007, 18:28

What oil do you run in your CRM scrubs?

Post by **scrubs** » 06 Nov 2007, 18:40

I run Putoline 10W 30 although a 5w 30 would be fine also
providing it dident leak

chronyx · Post by **chronyx** » 06 Nov 2007, 18:43

Is that just normal bike engine oil like you'd put in a 4 stroke?

Post by **scrubs** » 06 Nov 2007, 19:02

No, Two stroke and four stroke gear oil are different.
four stroke oil takes in to account that it will be lubricating
the piston also. Where-as with a two stroke, the premix/autolube oil
takes care of that.

also it may be worth adding if this is your first two stroke with
an auto-lube make sure the 'fuel oil' you buy is for injection
systems, it will say it on the bottle. pre-mix type is too thick.

Post by **Gwyn** » 06 Nov 2007, 19:40

Also worth checking Chronyx is the carb slide might be sticking, and the spring might be worn or broken

chronyx · Post by **chronyx** » 06 Nov 2007, 20:17

Cool thanks guys!!