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Discussion Starter #1
Can anyone help? My recent carb strip seems to have been a bit more cack-handed than I thought. The bike has started to be very jerky/snatchy at low revs, and the culprit is likely to be some crap in the pilot jets. I may just go the whole hog and buy three new jets. Do you know what size these are supposed to be for a 1995 Speed Triple running stock Mikunis and standard airbox and cans? 40.0? 37.5?

I assume that the standard setting is 1.5 turns out from fully home?

I will always bow to the wisdom on this forum. If you can think of anything else that could be causing the low rev snatchiness (is that a word?) then I'll be grateful to hear.

The chain's not new but is adjusted within tolerance. The rubbers carb rubbers to head and airbox are new and look properly seated (I thought about a leak).

As ever, many thanks in advance...:eek:


Trev
 

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check out some of the other posts in sport and touring section,I think the setting should be 2 and a half to 3 turns out if i recall correctly
 

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Check diaphrams for pin holes/seating ok.Check choke plungers are free and spring back.Free play in cable? Check fuel feed filter into T piece between carbs. Middle carb idle mix screw half turn out more? You can balance carbs manually..just adjust butterflies so their gap is the same,use a small dia pin/rod..just like feeler guage. Use idle adjust screw to slightly open middle carb,then adjust outer carbs so their the same. My tiger has a similar problem..since doing this,cleaning and setting float heights,its better,but hesitation still there. Maybe need to change rubber o rings?? Has anyone used the metric kit you can buy on ebay? They are nitrile. Lot cheaper than Triumph kits (albeit the bowl gskt)
 

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Discussion Starter #4
Check diaphrams for pin holes/seating ok.Check choke plungers are free and spring back.Free play in cable? Check fuel feed filter into T piece between carbs. Middle carb idle mix screw half turn out more? You can balance carbs manually..just adjust butterflies so their gap is the same,use a small dia pin/rod..just like feeler guage. Use idle adjust screw to slightly open middle carb,then adjust outer carbs so their the same. My tiger has a similar problem..since doing this,cleaning and setting float heights,its better,but hesitation still there. Maybe need to change rubber o rings?? Has anyone used the metric kit you can buy on ebay? They are nitrile. Lot cheaper than Triumph kits (albeit the bowl gskt)
I'll give it a go. When I had the carbs apart I looked at the diaphragms, and they seemed to be hole-free but I'll check them again. Carbs had new seals and o-rings fitted, and new 'witches hat' in line filters. Didn't check the idle mix.

How do you adjust the float bowl height. I checked the height and one was slightly off, but I lost the courage to bend the steel tab on which the float pivots. Too much mechanical sympathy is not always a good thing!

It's really annoying, as the bike runs so well at anything over 2500rpm, and it starts and ticks over like a good 'un.

Checking older posts it seems that it something that some bikes do and some don't. If this doesn't fix it then....I'll keep on trying until it does!

Thanks again.


Trev
 

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Float height is 14.5mm . He doesn't recommend re-newing all the o-rings..unless they show signs of wear/damage?? I was under the impression they should always be changed? I'm working on a set now,don't know whether to chance not changing them(£39 for 3 sets!!). Ive been told the main ones to check are the two on the floats..fuel can by-pass them if they're not a good fit.
I may try reducing spring length,or drill holes in the slides?
 

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Discussion Starter #8
Float height is 14.5mm . He doesn't recommend re-newing all the o-rings..unless they show signs of wear/damage?? I was under the impression they should always be changed? I'm working on a set now,don't know whether to chance not changing them(£39 for 3 sets!!). Ive been told the main ones to check are the two on the floats..fuel can by-pass them if they're not a good fit.
I may try reducing spring length,or drill holes in the slides?
To be honest, I sprung for three new seal and o-ring sets from Sprint Manufacturing. I figured that I'd only need to spend the £40 once, and that it was cheap for peace of mind. Of course now, I'm not so sure!

The two o-rings for the float are a doddle to fix and worth checking. Once of mine was almost split through. Trev recommends lubricating the o-rings prior to fitting and having done it and can see why.

Any idea what size the pilot jets should be?
 
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