MUGEN IMPROVEMENTS

[helisupp]

I am curious about Mugen modifications due to Delvey91 purchasing a CRM (AR) with Mugen parts installed.

After previously researching the subject I thought the AR did not benefit much from the Mugen improvements (a bit like a installing a dynojet kit on my VFR750) due primarily to the large AR valve.

Has anybody ridden a standard AR and a modified AR to see if they were more powerful or tractable, bearing in mind that the AR was designed for tractability did it trade tractability for increased power.

Only wondering............

[knackeredMk1]

AR Mugen 'upgrades' as far as I'm aware -

1). Cylinder head - Increase compression ratio from 6.7 to 8.0. Improves low/mid range and general efficiency of the engine. Needs 97+ RON fuel.
2). ECU - General very small power increase (I've got a graph somewhere which I'll post).
3). Engine intake rubber - Use this to remove the autolube system. (Intake - oil pipe, single throttle cable and blanking plate to put in crank hole where the oil pump sat).
4). Jetting kit - Small differences in jetting due to ECU and other changes. Many bikes get by without this.
5). Expansion chamber and silencer - General improvement in power, sound and weight as per other aftermarket systems.
6). Complete flouro pink plastic set.
7). Seat - Raises seat height by 30mm.
8). Forks - Have never seen apart from for sale on internet. Suspect much better springing and damping. Spring rate reduced from 3.3 kg to 3.1.
9). Shock - As forks. Has low speed rebound and compression damping adjustment.
10). Shock spring - As fitted to whole shock but available seperately. Rate reduced from 7.5 kg to 6.5.
11). 17 inch wheels - Supermoto.

8 - 11 all to make into a Supermoto.

[helisupp]

Regarding jetting, was the jetting changed to cater for premix , 2% oil in fuel (= 2% less fuel so smaller jet required.......)

[Sanchez]

[quote="helisupp"]Regarding jetting, was the jetting changed to cater for premix , 2% oil in fuel (= 2% less fuel so smaller jet required.......)[/quote]

I thought it would be more fuel needed (bigger jet)? To make up for the fuel lost

[knackeredMk1]

I don't think the jetting kit is related to premix.

With relation to premix you need to go for a bigger jet as part of what goes through the jet is not burnt so you tend to run lean. I think Mark just got mixed up in the writing.............

[helisupp]

No not me, never, mixed up, premixed up more like it.

[Active Rascal]

My old AR was pretty much standard apart from a full DEP.

The new CR/CRM has MUGEN head, ECU and jet kit, Aktive reeds, Pro-Circuit front pipe and DEP rear, CR250 airbox/filter. Yes it feels very powerful, but hard to compare as the ride is completely different and it's much lighter. However, when dyno'd, it only kicked out 29BHP I think at the wheel, so I wouldn't say all the mods have vastly increased top HP, maybe increased across the range and smoothened things out a little.

Shaun.

[delvey91]

As far as i can tell this one has abit more bottom end than i recall. Otherwise the top end seems about the same. Although im stripping it down and have found the carb to be in quite a state !! So will need to sort that 1st. I think the previous owner may of drowned the bike greenlaning then left it.....



Also my old CRM AR made 34.4 at the rear wheel albeit with sm wheels fitted.

http://www.youtube.com/watch?v=etHkB3thaB4[/youtube]

[helisupp]

From the amount of mud you have had in the carb and engine /gearbox, just what was the bike buried in.

As you purchased the bike in a classified Advert on ebay from a dealer can you not go back to the dealer and ask for financial assistance on the rebuild as it was not fit for purpose, or was it sold to you as unserviceable..........if it was sold as a normal sale (even without warranty) you would have a case.

[delvey91]

Im not that fussed, was sold with the spare or repairs clause...I know that means i could still have a case but the guy didnt know, the bike still ran absolutey spot on apart from cutting out at idle. 320 in parts and half a days work ive got a bike that will probably see me though all of 2013's greenlaning without further issues.... touch wood ! On the 250 exc i used on the lanes last year the bills were scary, adding up all the engine servicing, fuel, 2 stroke oil, consumable items ie tyres brake pads and insurance MOT and tax i spent £2487 on that bike alone Massive amount !

[helisupp]

Well I enjoy these bikes better than my last collection, spent my life polishing and cleaning every weekend, all in showroom condition, sold the lot of them 2 years ago.

These bike not really relevant on CRM forum, but gives a background to previous ownerships, after these the CRMs are simple.

[Rustyone]

Some proper nice old tools there