Flatslide woes

[Foz]

Any knowledgeable people out there with experience of flatslides ??? 

  I've been  running rs38's on my 1216 bandit for a few years now , they work well. I recently bought some rs36's to try , they have the same diameter inlets stubs so fit into the rubbers I've been using with the 38's , they fitted ok, balanced up ok and in the garage revved cleanly. The problem started when I used the bike on the road , the revs hang up constantly in that the bike tickover at 3 k and creeps up to 5k , stop at the side of the road wind the tickover back down to 1k then once on the move it reverts back to 5k. 

  I've changed inlet rubbers, changed the carb clamps so I'm pretty sure there's no air leaks on the inlet side , tensioned the return spring to its stiffest setting to ensure the slides shut . Any suggestions ??

[Captain Chaos]

the obvious... throttle cable too tight?

[SiBag]

Are you using a push me pull your throttle?

[Foz]

Motion pro push pull throttle , all tension removed ,slides shutting against Spring tension. I thought it may have been engine vacuum holding the slides open  hence why I took the slide Spring to its stiffest setting but it's not. I can set the tickover at 1k and within half a mile the tickover has crept upto 5k . I pull on the drive with it doing this,hit the kill switch so I could see the slide position Incase the tickover screw had wound its self in 5 turns but no the slides were shut as they should be.

Edited May 9, 2018 by Foz

[KATANAMANGLER]

Are the slides plastic or metal? The early RS series had plastic slides which wore easily and leaked. The later ones were aluminium. Any lateral movement in the bushes on the throttle linkage bar?

[Foz]

The slides are aliminium and no movement in the bar.   It makes no sense , everything moves as it should 

[Gammaboy]

Second hand RS36s? Sounds to me like the worn bodies 370 Steve was suffering from on his first set.

[Foz]

That’s the thing , they seem like s very good set, no movement , no excessive chattering . I’M sure it’s something simple 

[Sheep]

I suffer from similar issues with mine...I have never got it to idle like factory carbs but I wouldn't say it is as bad as yours.I always set my idle speed when the bike is warm and often find myself having to physically turn the throttle back to lower the revs when coming to traffic lights for instance,(I have removed one spring one hole back mind you)....It is something I have lived with but after faffing about with jets etc to get a happy medium I have come to the conclusion that a new set will have to be purchased next winter....I am passing too much air through worn slides for it to run as Mikuni intended....However,i do hope that £850 ish for new carbs will sort it out once and forever.

[Foz]

My old 38's tickover fine , Rev cleanly, return to idle perfectly. These 36's idle perfectly, balance perfectly, run cleanly then you set off down the road and the tickover increases with my revs , it won't do it blipping the throttle in the garage . So you pull over ,wind the tickover down to 1k , blip the throttle and all is good until you set off again then it all repeats again. 

[KATANAMANGLER]

I had a similar problem with an old set of 36s on the slabby last year at Donington. I thought it was the cables but the cure ended up being the addition of a locking nut to the idle adjustment screw, which had worn a little slack on its thread. It was winding itself out.

[Foz]

Would it wind itself out within 1/2 a mile of use ? I stopped the bike whilst it was doing it and then removed the carbs expecting to see the slides being high but they were at the bottom 

[KATANAMANGLER]

By the end of my first lap at Donington the revs were up at 5000rpm.

[MeanBean49]

When its hanging up try and push the throttle lonkage tube downwards with your finger between 1+2 & 3+4 see if it drops. Doesnt take a lot of wear in the tube bushes to make them hang up badly. It can be barely noticeable without the motor running

[370steve]

2 hours ago, Foz said:

That’s the thing , they seem like s very good set, no movement , no excessive chattering . I’M sure it’s something simple 

so were mine

[Foz]

What were your symptoms Steve ?

[Foz]

1 hour ago, MeanBean49 said:

When its hanging up try and push the throttle lonkage tube downwards with your finger between 1+2 & 3+4 see if it drops. Doesnt take a lot of wear in the tube bushes to make them hang up badly. It can be barely noticeable without the motor running

The thing is Rob , it tickover perfectly, will rev cleanly and drop back to tickover perfectly. Ride it up the road and the more revs I use the higher the tickover goes up to.  3k on the road 3k tickover, 5 k and 5k tickover and doesn’t drop back down . It’s like the tickover screw is moving but it’s firm 

[370steve]

17 minutes ago, Foz said:

What were your symptoms Steve ?

would hang revs no matter what i did, when i talked to Allens they said it was not un common for RS's with worn slide/body to do it

[MeanBean49]

17 minutes ago, Foz said:

The thing is Rob , it tickover perfectly, will rev cleanly and drop back to tickover perfectly. Ride it up the road and the more revs I use the higher the tickover goes up to.  3k on the road 3k tickover, 5 k and 5k tickover and doesn’t drop back down . It’s like the tickover screw is moving but it’s firm 

Thats exacly what one i was stuck with was doing. Was a nightmare

[Foz]

Did you solve it Rob ? Or give up on them 

[MeanBean49]

4 hours ago, Foz said:

Did you solve it Rob ? Or give up on them 

I temporarily fixed it by putting some heat shrink on the shaft to take the slack out and it proved that was the issue. Changed to turbo after that. But I think you can get new inserts/bushes for each body to fix it properly

[370steve]

http://oldskoolsuzuki.info/forums/index.php?/topic/8410-slabby-vm29-flatslide-carbs/

[Foz]

Spoke to Allens earlier and he said it's either wear in the body, emulsion tubes or there's a gasket between the body of the carbs . After dialling the cams in earlier today , I tightened up the body screws a little and briefly re-fitted them this time I couldn't get them to hang up in the garage as I previously could so possibly the problems solved. I re-fitted the 38's as I need to see the difference with the cams dialled in. You wouldn't believe the settings the bandit sprockets were running at on the gsxr cams 

[370steve]

2 hours ago, Foz said:

 You wouldn't believe the settings the bandit sprockets were running at on the gsxr cams 

were they way out? what GSXR cams?

[Foz]

Gsxr cams with bandit sprockets fitted, that's how it's been since it went 1216 .Today the ape adjustable sprockets were fitted and dialled in at 105/107 on the bandit sprockets it was something daft like 99.5/114