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Everything posted by Oilyspanner

  1. Sorry for the delay, I've been fiddling about on another little project. My k and n was fitted when I bought the bike and a previous owner had hacked around the inlet with a knife !! I trimmed a yoghurt pot and siliconed it in the inlet, this gave a 50mm orifice and a radius going into it. It sounds like you may need to go up a size on the pilots, but if the idle and gentle cruise are okay, leave it until you have enough time to remove the carbs again - it's a bit of a pain removing them with the airbox. If you can find a decent setting with DJ needles and std e.tubes don't question it ! Dj needles have a different taper to the std needles, so probably will go rich quickly. Go with what the engine likes, I wasted a fair bit of time over thinking the jetting. Also make sure the engine is fully up to temperature when settling on the jetting, several times I thought I'd sorted everything and then went on a long ride and my 'wonderful ' carburation... wasn't so great.
  2. most of your running will be on the needles, if you've got a stable tickover and a half decent needle position you can ride it and figure out if any of the circuits need to be leaner or richer. I take it the dynojet kit came with needs and emulsion tubes ? if you use their needles, you have to use their emulsion tubes and vice versa, else it's near impossible to tune. Altering needle position is pretty easy, try a notch higher and lower, the engine should like one or the other more. Early in my ownership I had a k and N in the airbox and an Akra - I used 130 mains, std needles lifted 1 notch and pilot mixture screws out an extra half a turn..... obviously you have a DJ kit so sizes will be different, but the process will be similar. The good thing about using an Akra is that you know they're developed to deliver a smooth delivery, so that's one known, it won't be at fault. Does the bike run okay at any revs and throttle ?
  3. I'm well in my 50s and still a hooligan at heart, more considerate these days, but my bike is a bad influence
  4. An oil cooled engine won't pull 10800 in top.....unless it's very low, they drop away after 10k. The point of mph/1000 revs is that you can work out what would work for your engine, where the torque is, revs at cruise speeds etc. Our engines are vibey around 5,500 rpm, so it's good to avoid that. A 16 mph per 1000 top gear gives 80 mph at 5000 revs - relatively relaxed and away from the worst of the buzz. Road gearing is a compromise and depends what you want, acceleration, or more relaxed cruising.
  5. Just got back from helping my elderly parents. I've just realised that the primary drive will be the same, not changed to 750r - this would make more sense .... 1.565:1 not 1.74:1 15:48 gives, 6th 148mph 1st 58mph at 10800 revs But Joseph's 16 : 43 looks really good 1st 6.44 mph/1000 revs 69.6mph 6th 16.31 mph/1000revs 176.24 mph at 10,800 revs
  6. Forgot to add, definitely don't use 14/48 !!!!!
  7. Have just done some calculator work, using Joseph's ratios and a tyre circumference of 79 inches. 16:43 final drive gives 1st gear 5.8 mph/1000 rev = 62.64 at 10,800 revs 6th gear 14.68 mph/1000 = 158.54 at 10,800. The speedo would read more than this. Std 1127r 5th gear is 16.15 mph/1000 revs by comparison. If you can fit a 17t front sprocket with a 43 rear = 6th 15.59 mph/1000 & 168 mph 1st = 6.15 mph/1000 & 66.51 at rev limiter It's not worth doing the other ratios as they'll be closer than the std box anyway. Depends what you want ?
  8. As sago has said - you need to work out at what throttle. Here's what I did to know which percent of opening I was using, I rubbed some of the markings off while testing, but you get the idea.
  9. Makes sense, standard parts are expensive, not renewing them goes some way to paying for the rs carbs. The rs36 carbs are easier to set up and parts are readily available
  10. Oilyspanner


    I've spent several years peeing around with the needles, worn needle jets/emulsion tubes etc. My findings back up what G1460 said. You need spacers that hold the needles central and within spec carb slide guides, mine were worn, too much slop and the needle will be moving all over the place, causing wear and incorrect fuel monitoring. You'll notice a 0.05 mm difference on the needle/needle jet orifice gap.
  11. If you can see that the emulsion tubes are oval, they'll be pretty far gone. You can drop the needles down to offset the richness caused - I've done this a couple of times, even gone down a pilot jet size because it caused problems there too.
  12. A bit late on this one.....did some thinking on this one a while ago : particularly on a faired bike, at speed you have high pressure on forward facing surfaces, but down the sides there's a drop in pressure. At high speed the engine requires large amounts of air, which further lowers the pressure within the bodywork..this would muck up fuelling that seems fine on a static dyno, so any air that can be fed from the high pressure area towards the air intake is a good thing..it lessens the potential losses at high speeds. Engines don't drag air in, they lower the pressure within them and it's the far higher surrounding pressure that rushes in to balance the pressure imbalance...if the surrounding air pressure is lowered, engine efficiency drops too.....so the tubes do help !
  13. The info is already in this thread - but one thing that's wrong is that 40c0 is gsxr1100 k and l, 41c0 is 1100m and n models - usa m and n used the earlier 40c0 inlet manifolds, as they kept the 36mm bst carbs instead of using the 40mm bst carbs like the rest of the world market. The dot heads used different shaped inlet manifolds, so ones from other models don't line up so well..at least as standard.
  14. I've got an old GS650GT whose inlet manifolds are hard, I'm going to soak them in an oil of wintergreen (methyl salicylate)/ isopropyl alcohol mix for a couple of days - this rejuvenates the rubber, it's been used by some people I trust, so should work fine. My 1100N's carbs have been off so many times the rubber hasn't had chance to think about toughening up ! I often put a thin layer of rubber grease on the rubber, this may help stop the aging process a bit.
  15. The 1990 and 1991 750s have an extra row compared to the 1100s - the taller 1100 engine doesn't have as much space above the headers because of it's longer stroke. This also tells us the frames of those years are the same size.
  16. I wanted to know how to work it out, so I could understand it myself ......my wife's a maths teacher too, there's no hope !
  17. There's several types of Nitron, the ntr1 doesn't have a remote res. It works really well, I had that one first. I've since bought their fancy race one, that has a fixed reservoir - it came up second-hand , it had been on a race gsxr600L4 - I had to swap the bottom link to the clevis type link - this is why I know about the 600/750 shocks _ the spring rate is suitable too. The 1000k5 is very long as I remember, 330mm or more I think, I'm sure there's a swaps thread in the vault maybe ? You can make shocks fit with different length linkage rods/dog bones, but if you go too far the main linkage angle changes, so the shock doesn't work as well. Anything works better than a shock with no damping though.
  18. Something I did to quickly work out true speed in each gear _ this is for gsxr1100 k-n and b1200 Quick calculation helper numbers. 1st gear 0.25381 2nd gear 0.37099 3rd gear 0.4841 4th gear 0.58182 5th gear 0.66275 Then measure rear wheel circumference in inches - you multiply with this number. work out final gear ratio, you divide the number by this. This give mph per 1000 rpm. Often used final gears and ratios 14 : 48 = 3.43 15 : 48 = 3.2 15 : 47 = 3.1333 15 : 46 = 3.0667 15 : 45 = 3 Here's 4th gear speed for my bike for example. 0.58182 ÷ 3.0667 × 79.5 inches = 15.08 mph per 1000 revs For 5th 0.66275 ÷ 3.0667 × 79.5 = 17.18 mph per 1000 rpm All I did was work out most of the calculation minus final drive and tyre circumference , I just like working things out .... hopefully someone will find it useful too.
  19. I bought a Nitron shock for my 1100n, best thing I did early in my ownership of my bike - any decent shock will make a big difference. The standard shock is only 312mm eye to eye, a bit longer is good - the gsxr600/750k6/7 shock is 320mm long , has good spring weight and the correct fitting at the bottom, the later shocks have an eye at the bottom link.
  20. The angle of your swingarm looks greater than mine. I've got an 1100N, with gsxr750 k9 forks, 750L2 wheels and a Nitron race shock - I kept the std swingarm and linkage, so a few similar things. I've 12mm of static sag on the rear - the amount the shock compresses due to the bike's weight, if you have next to no static sag, ie the shock is near topped out all the time. Lift the rear of the bike at rest and there should be some movement until the shock is topped out. The shock has a 475lb spring on it now, the 500lb/inch spring only worked when I was really tramping on. The forks still have the std springs in them and have 30mm of sag, I think the 750k7 had .95kg springs in them, the 1100's were around .75kg, so plenty firm enough. My bike is 96lb lighter than it was and handles really well, feedback is great front and rear, they can handle really well. I expect it's just in the set-up
  21. You'll have a power delivery full of holes, that was my experience trying to make my 40mm carbs work without the airbox - I used the std velocity stacks with ramair filters squeezed over the ends, I even had a factorypro kit for this conversion …. factorypro made the kit to work with k and N dual filters - still think the airbox is needed, or some sort of airbox to make the 40s work well. I like a challenge and thought the weight saving doing away with the airbox would be a good idea … I failed. The bike needed 155 or 157.5 main jets to pull well up top - still not as good at any point as the airbox, pipercross filter, 145 mains, special needles and 40 pilots I have now - sorry sfc, it won't be easy. Flatslides are pretty easy to set-up for many altered filter/no filter stuff. Oily
  22. She looks mighty fine Dezza ! Such a good looking frame, lovely quality - unfortunately Captain's magnum is probably the closest I'll get !!
  23. Main benefit is as already said - makes space under the tank, weigh less and it's easy to 'clear the decks' when you do valve clearances. Did mine quite a few years ago, zero problems.
  24. Welcome to the site. Just 4900 miles ? Probably a typo. Have you looked at the plugs - a low speed running problem will show on the plugs, normally sooty. You say you replaced all jets, does this include the needle jets ? Check your plugs to narrow down the problem, then you can move in the right direction.
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