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[jefrs]

Nigel - glad that's sorted out. I've heard tales of wobbliness, reviews of new bikes where the bearings' play should be good; probably regurgitating old phrases learnt by rote. I was putting the improved stability down the the increased rake of the latest one, the current 'straight' forks have some 10mm less lead but have the taller 19-in wheel and the forks have progressive springs, I think they're maybe a trifle longer. By 'rock steady' I mean I can take my hands off.

I've tested fast cruise speed on Europe's longest dual carriageway, the A34 :] it will cruise at 70.

The martian antennae mirrors wobbled, the bar end does not, at all.

The 70 legal limit is usually experienced as a minimum speed meaning an 80+ capability and a modicum of common sense is needed to keep out of trouble.

To be honest I haven't a clue what mileage I'm getting but I don't get anything like 89mpg; I'm mainly dodging between 3rd and 4th so I don't expect to.



One other thing to to is check vertical and horizontal wheel alignment, not count tension plate notches - I found my plates are not symmetrical mirror images. There's only a couple of millimetres vertical tilt adjustment when you're clamping the wheel up. If the bike tips when you release the bars then something is out of kilter.

[jefrs]

I've heard tales of wobbliness, I've never experienced it on this bike, it's nearly as steady as the Honda 400/4 which handled like a cat.

Jeff

[Trev]

I've a 2008 efi Royal Enfield, I think the C5 model but not 100% certain - the latest hydraulic valve motor with chrome tank. Anyway I digress, I've had it for just over two years and use it mainly for back lane & B roads, often two up, 40/50 miles with the occasional longer trip (up to 100 miles) thrown in.
When I got it I did oil & filter change for decent synthetic oil, junked the hideous standard silencer for a shorter less restrictive one and bunged in a K&N & NGK Iridium plug. This perked the thing up a bit and pulled top easily everywhere even two up so decided to go up one tooth to a 19 on the front.
This has made the bike a comfortable cruiser at 60/65 and even 70 (which it pulls almost anywhere) is not too bad although a 20 dual carriageway stint at 70+ didn't feel right for me or the bike. The revised gearing and extra bhp (+1 or +2!!) even allows occasional forays above 70 when my sportsbike riding alter ego tries to take over ; )
It still plods along nicely at 50/55 two up taking most hills in it's stride at that speed but one of the best things about the gearing change is that it has made 4th gear useful for the occasional 'high speed' overtake. Whereas previously if I was following something at 50/55 and wanted to get past it meant either screaming it in 4th or winding it on in 5th for even more relaxed acceleration now I can use 4th fairly comfortably up to 60, even a bit beyond, before changing up into 5th once overtake complete.
Given that my mods won't have made a massive power/torque difference I would imagine that even a standard version could pull a one tooth bigger sprocket and, at less than twenty quid, I suspect that could be the besxt £/performance mod you could make on a modern Enfield

[nigelphoto]

Trev - C5 introduced 2009 and had a single seat and no pillion footrests as standard. Go to the lhs of this window and lci k2 down 'parts catalogues' and you can easily find the model number of your bike.

[Rattlebattle]

Thanks for that, Trev; very informative, You've convinced me to put a 19 to toothe sprocket on my C5. Will I need a longer chain and how big a job is it? The engine layout is not like all the Brit bikes I've owned where the primary drive has to be dismantled to change the gearbox sprocket. Are any special tools needed for the job? Any advice appreciated.

[Trev]

Thanks Nigel, I keep forgetting which model mine is, I'll check the handbook tonight and post

[Trev]

Rattle, my chain is the original and had stretched a fair bit even after only 3000 miles so I managed to get the 19 tooth on by just moving the wheel forward nearly as much as the adjusters would allow. Pretty straightforward provided you have some mechanical capability, you have to drain the oil to remove the right hand engine case, I did an oil & filter change at the same time and used a new gasket from our our hosts. Make sure all mating surfaces were clean and the gasket is not kinked before putting back together and tighten the sidecase bolts evenly. After your first run out check casing bolts again in case they need a tweak, I have a torque wrench but not really needed for side cases with gasket, 'engineers feel' is good enough.
Good luck - Trev

[Rattlebattle]

Thanks Trev; it sounds pretty straightforward then. It'll have to wait until we've moved house, by which time maybe the chain will have stretched a bit more.....it'll be interesting to have a nosey inside too. Thanks once again.

[jefrs]

H do some chain and cog kits (qv) i.e. correct length of chain recommended, differs with bike model. The pitch is 1/2-in so one extra tooth is one half link or half inch more chain, in practice move the wheel in by 1/4-in. Two more teeth means two half links, another inch of chain, maybe a new chain or move the wheel in if you have enough room. It's geometry but the handy measuring tool is the chain pitch.



We can't fit a smaller wheel sprocket because the brake drum is in the way. CGT is different. So all we can do is fit a larger engine sprocket. Back of beer mat calculation for theoretical top speed is something like 19/18 x 85mph = about 90mph; ratio of new sprocket to old sprocket.

[jefrs]

Nigel, you have fitted a 20T to the 2011 C5 which is an earlier model to the 2013/14 and a later one to the first C5 model of ~2009. There are some cunning differences. I believe you had to file the crankcase to get the 20T in.



How much and where did you file?



I get a beer mat guesstimate of mid nineties top speed (maybe 96 at red line, 5500 rev limiter) but doubt there's enough power in standard trim to do that, nor sitting upright. The primary, gear and secondary ratios are, complicated, but I think in gear ratios not overall, so 20T would effectively give 4th a 1:1 same as original 5th (18/20=0.9). That seems a little long for 4th to me; what is really needed is a wider set of gear ratios. I'm thinking 19T seems sensible and needs no crankcase modification.

The other way is fitting a bigger dia back tyre. The B5 has a 19-in rear with a 17T and a longer chain, the C5 has 18-in rear with 18T; net result near enough the same.



To fit so I believe, rear wheel is moved forwards to slacken chain, outer casing off (oil change , tabs folded back, nut off and sprocket pulled. [It says three leg puller in the workshop manhuel (special tool) but I've only a two leg one] Is this correct?

Pulling teeth. Is this bike dentistry?

Jeff.