Reservoir-dog

At first I though it was from some kind of exhaust leak but now it seems like it comes from the rear right hand side of the engine. The noise only comes on when the engine runs hot. It is difficult to describe the noise. The only think that comes to mind (I know it sounds stupid) is that it sounds like a canary whistle in a intermittent kind of way. How I can post a pic and pin point the part of the engine?

Going back to the topic of getting a bit more poke. The xvs 400 has 2 carbs right? So if the xvs 125 had 2 stock carbs, one per cylinder,you would gain a lot more power. I'm wondering if the the xvs 400 manifold could somehow be adapted to the xvs 125...... Just wondering........ Maybe only Oldtimer could help but now he is busy with is new toy. LOL

Probably your inner tube was from a different make than mine with a shorter or longer valve. From my experience the only probable way would be loosening the nut ring around the valve and force the air line in. Paulwhite, Thanks for the tip. I had no idea that inner tubes with a right angle valves existed. Thanks mate. Anyway for 6 quid the adaptor does the job.

Thanks Ttaskmaster but I've just bought the valve adaptor from a tyre shop in London this afternoon. £6 job done. And yes, I was told not to leave it on the tyre as it tends to let air out. With such a large wheel rim and inner tube, the adapter is crucial because the air valve sticks out straight making it quite impossible to place the standard air lines at the right angle. I was expecting that Yamaha would include the adaptor with the tool kit.

I will . Many thanks once again.

Thanks barkwindjammer for your help. I think that is the only solution. Many thanks once again

I just can't do it. I've been in two different petrol stations, BP and Shell and can't get the air line at the right angle. I tried every possible position but the spokes are in the way or the mud guard is in the way. Is there some kind of adaptor missing in my tool kit? Help would be much appreciated Thanks

I have unsuccessfully done some googling trying to find out if the xvs 125 share the same engine as the xvs 250 but with smaller barrels and pistons. In other words, if it would be possible to upgrade from 125 to 250 by a bolt on replacement of the lower part of the cylinders. Not that I'm planning to do that I'm just very curious. Can anyone shed some light on this? Many thanks if you can

Update Today I had the stock 16 tooth front sprocket replaced with a 18 tooth one and what a joy: The best decision ever. It's like riding another bike but better. So much smoother. Beautiful engine balance through the gears and cruises at the same speeds with much less revs. To give you an idea I would say that now I can cruise at 30 Mph in 4th with less revs then before in 5th and somehow when you accelerate it feels like you have more torque, and when you change to 5th.......Heaven.... really smooth. You don't get the feeling of loss of power whatsoever. Guys and girls I recommend this easy and inexpensive transformation that doesn't even involve fiddling with the engine. Total cost was: Supplying the front sprocket (them not me) Labour to replace the front sprocket MOT Engine oil top-up (serviced last month) £60.00 The next and final chapter will be the main jet replacement from stock 90 to 100. I will keep you guys informed.

Thanks for the pics. It's always useful to see how the bike looks like once stripped. Opinion? hmmmmm

Update A decision has been made. Definitely 2 tooth up front sprocket (from standard 16 to 18) is the way to go to achieve the improvement I'm seeking. Thanks to oldtimer that direct me to this link http://www.yamahaclu...oke/page__st__3. No need to invent what already has been invented and tested. Fantastic job and shared information by Markyboy27. However there are some modifications that Markyboy27 did that I'm still not 100% sure, as for example the removal of the in line fuel valve. I just don't understand what this valve does and why it restricts fuel to carburettor. So I still have to workout that one. Regarding the EMGO air filter is another one I'm still not sure if it make that much difference. I've owned, and fiddled, in the past with a VW and a Porsche 912 flat four air cool engines and to my experience this K&N filters never really shown a noticeable improvement in performance. In another words a decent or stock filter did the same. Yes they may do but together with another modifications like polished intake manifolds, polished heads, bigger valves and bigger bores. Regarding what Markyboy27 did about jets (100 jet to replace 90 standard) I agree 100%. I know every bike , even same make and model, is different and feels different but based on my bike my opinion is that the xvs runs to lean. Take for example the time that you need to maintain the choke on until the bike runs smooth. To me means to much air/to less fuel and therefore a bigger jet will cure that. So maybe no need for alterations with the air filter but definitely with the main jet. There are a lot of people questioning, in this and another forums, if the xvs is somehow restricted. My answer would be yes by the meaning of lower gearing and jet carb restriction. Tomorrow I will order my 18 tooth front sprocket. I will then run it to get the feeling of the changes. The chance are that by the 25th May, MOT time, I will have the jet replaced. As I said above I think that the guys at the factory panic a bit when they had the idea of making a 125 on a 250 frame. I will keep in touch

Thank you very much Oldtimer you are absolutely right. Is a matter of trial and error. I'm inclined to go +2 on the front sprocket to start with and see how it goes. To me is not a matter of more speed is a matter of achieving the same speed with less revs therefore making the bike even smoother when cruising. Today for example I did a stretch of the North Circular Road at about 50 mph (I was going to the Ace Cafe but turn back due to rain LOL) and I found myself looking for another gear as I though that I was in 4th. I also noticed that cruising in 5th under 30mph, like my bike does comfortably, is not quite right. I honestly think that the guys at the factory panic a bit when they had the idea of making a 125 on a 250 frame so they gave it to much ratio. Thanks all for tips

I have no doubt that the this little big bike could improve it's performance by ticking with the gearing being the easiest way starting by changing the front sprocket. First of all because the transformation remains hidden (no obvious need to inform your insurers LOL) as well as little changes need to be made to the chain (wheel/chain adjustment will allow that). My big question is 1 or 2 teeth? Unfortunately I haven't yet found a bike guru in London that could show me light in this particular dilemma.

Hi There I've just bought a 2004 6k miles xvs 125. I've only done 53 miles all through London traffic and I always avoid to use first gear because I feel it much to short to use in traffic. I am considering changing the front sprocket making it bigger. Maybe just one tooth but I was told that just one tooth will not make to much difference. Any feedback on this?