SORRY ABOUT THIS... BIT OF A NOVEL REALLY BUT PLEASE STICK WITH ME IF YOU CAN.
Ok. Time to really go from the ground up here and explain up to where we have got to right now.
I bought this bike from someone who rebuilt it from the ground up. He claimed there was an issue with the transmission so it had to be stripped down so he figured why not spruce it up at the same time.
Realisticly I should have heard the alarm bells ringing right there and then but he'd done such a nice job on it i was blinded.
It later turned out that all the reciepts I have are listed to North Devon college, where he works.
I put 2 and 2 together and now firmly believe that this bike of mine was the college project.
No big deal. Engine runs great and only really a few minor issues around the rest of the bike... like an irritating buzz rattle at 5.5k revs emminating from the front of the bike but I can't tell from where. At first I believed it to be from under the speedometer and rev counter (since they are quite flimsy) but now an not so sure, it sounds more like under the tank or near the radiator. Regardless its a very flimsy sounding rattle so I feel its only something small and cheep and thus not making me immediately fear for my life. Although identifying it's source would greatly cheer me up. The front and rear shocks really are quite firm. I'm not sure if the rear springs are the correct set for the shocks. It ride's ok until you hit heavy bumps on bends and then it tends to throw about a little (keeps me on my toes, no overcooking it on bends is a good thing really lol).
The carbs... have been a nightmare since I got it!
At first I just believed it to be a matter of tuning. The guy had only barely put a 100 miles on it since its rebuild (I don't think he was counting on selling it so fast. He had a 7 day listing and I offered him cash early into it). He had replaced the standard exhausts with these that you see on the bike and replaced the air filters (a'la ear shave I presume) with tapered pods. However upon closer inspection I can firmly say I don't know what make they are. My mechanic says he does not think them K&N's but more likely some cheap aftermarket variety.
The guy I bought the bike from did give me all the old air intake stuff and filters at least, though they are fairly tattered. Some of the rubber would need replacing and some of the plastic needs some cracks gluing shut.
The best way to describe this initial problem was to say it pulled nice and torquey up until about 4.5k then it would fight against the throttle and sag in power until you hit about 7k... then it would scream off like a rocket. Now that I look back I can see it also had an underlying problem of not being able to retain a steady throttle however this was heavily masked by the power issues.
I contacted the guy and he said that he'd researched his info from this very forum and that he had upped the jets to 40/140 and a 1mm washer as a make-do for 2 shim's (he was at least kinda right as upon research I found that a shim is roughly 0.5mm and so 2 of them would equate) as this was the suggested place to start.
I posted here and Lance very kindly took the info that I gave (which may have been a little incorrect as I initially believed the filters K&N's) and gave me a suggested up-jet of 42 pilot jets, 147.5 main jets, 2 shims under each needle and 3 turns out on the pilot screw. Well the shims and the jets worked well but the 3 turns out was too much (my mechanics opinion not mine0 so we settled for 1.5 turns.
This immediately sorted one very important thing out! This allowed smooth power distribution over the entire rev range. 1k-11k pulling well with a power band between 6k and 9k. Fantastic! Off like a rocket!
Could not keep a steady throttle for the life of me. The bike either wanted to just go or nothing. This is fine if I just want to accellerate or coast down everywhere (believe me its quite fun but mostly illegal lol). So back to my mechanic friend it went with more investigations.
One of the diaphragms had a split in it. We replaced both with new ones... it made no difference.
The float levels were 17mm out!!! We played with those... it made no difference.
Upon testing different shims my mech took it out and it died! He checked it over and found one of the rubber connectors to the pod filters had split!
A brand new pair of them has just arrived (because they must be replaced) meanwhile, to the old one, he has glued it back together for me so that it will run at least until he gets back from holiday and we fit the new boots.
Before he went away on holiday he stuck a pair of socks over the air filters!!! The bike will now ride at a constant throttle!
However I can really only accellerate gently. If I open the throttle quickly and full it wants to hop down the road! It coughs and pops violently and the power back's off considerably.
So here I am.
At least now if I need to I can ride my bike to work. It will even quite hapilly get to 70mph and sit there too
But my fuel consumption doesn't justify the innabillity to accellerate and have fun.
So........ what's with me taking in too much air?
I'm so stuck here. Also this whole ear shave thing. Whats the comparisson to a standard system fuel wise? At the moment it seems I can just about get 90 miles out of a full tank. That's really not very efficient and given I have to ride 66 miles every day I'm wondering if I should just quit on this ear shave thing and retro-fit the standard filter system back on and jet/shim to suit? I can handle the 90 miles to a full tank if the damn ear shave is working propperly or if there isn't much difference if it were the standard air filter intake system. Am I using too much fuel or not?
I'm beginning to think maybe I should just sell it and buy a Rover Metro.
.... please help me, I'm loosing the will to RIDE!!!
42/147.5 2 shims and 1.5 turns of the pilot
Pods, non standard exhaust
What you see is all I know