Side Gapping Spark Plugs

This is my most unexpectedly good finding of the week. "Side Gapping Spark Plugs". I never heard of it before, so as many of the other good veteran riders in Yamaha SR 500 Forum. When i read this article it was something tempting and scary at the same time to try it on my sweet "ebony". Well, no pain, no gain right?. I had a spark plug laying around which is from my Virago 750. They were NGK BPR7ES. Currently my SR 400 is running on NGK BP6ES Spark plug so i removed it and kept it aside. Side gapped the NGK BPR7ES and put it back in the bike.

Well i guess what the old skool racers said and done was true. Side gapping clearly increased the horse power of the bike, it pulls better, idles better and i thin the fuel efficiency has increased as well. Someone might now be wandering, why the heck they initially make stock plugs like that. Well i have no idea why! but i know there are double ground strap NGK's coming with most toyota cars so it can't be that harmful. Some how the life of spark plug will decrease , but with above advantages i wouldn't mind changing my spark plug quicker than they use to be.

Only downside that i will go back to standard gaping is the engine heat. I felt that the heat that generates in the cylinder dome has increased a little bit. I think i have misunderstood it because the moment i felt it, i was riding the bike in a kind of bad condition road at slower speed, probably riding slow has heated up a little than normal and i am too paranoid over it.

here's the link with a picture guide on how to side gap a standard spark plug

http://www.instructables.com/id/Save-Gas-And-Incerase-Horsepower-By-Side-Gapping-S/

PS : I am not liable for any damage caused by doing above to your machine or your self.... So you are on your own here. :P

Yamaha SR400 User Manual in English

I was looking all over the internet for some documentation about Yamaha SR 400 in English and believe me it was a difficult task. I looked for the haynes manuals etc and none is freely available. I found this SR 400 user manual that was completely in Japanese. It contained all the basic and necessary information like, company specified spark plug, gap, information about sprocket and chains, tire size, quantity of air that should be in the tires etc. So i manage to translate the japanese manual to hopefully understandable english. This is not perfect at all but most of the information we are looking for is here and to my opinion is understandable. So here goes, i thought i'd share it with another weary rider who's looking for this information about their beloved SR 400's.

http://www.2shared.com/document/Ju-UGhV3/sr400jaen.html

Yamaha SR 400 Carburetor settings ( Stock BST 34 )

I've been through hell to find some real stock settings and information about the SR 400's stock carburetor BST34 Mikuni. You might be wandering what the hell i am talking about. Alright let's be clear, SR is a famous bike, SR500 and SR400 is pretty famous but search the web by your self if you can find information like Stock Pilot Jet Size, Stock Main Jet Size etc of the SR 400's that came between 1988 - 2000. The stock carburetor is BST34 Mikuni diaphragm CV Carburetor. i am sure it won't be easy because SR 400's are rare outside japan and asia, most of the documents including user manual etc is in complete Japanese. That is not the only reason, nearly 90% of the SR4's out there are not running on stock carbs. They are running on alternative slide carbs from many other manufacturers.

So i thought i will share the information i found out about the settings with everybody who search for it. after setting my bikes carburetor to these stock specifications, it started giving more power, and the problem it had of the RPM is going up and down on it's own in idle has solved. So here goes. If you want any other information please do not hesitate to ask, i'll be happy to help.

VM32SS Slide Carburetor (Model Years 1978 ~ 1987)
Main Jet - # 280
Pilot Jet - # 25

BST34 Mikuni CV Type carburetor (Model Years 1987 ~ 2000)
Main Jet - #162.5
Pilot Jet - #45
Float Height Settings - 12.5mm ~ 13.5mm
Idling Speed - 1350r/min

BSR33 Mikuni CV Type Carburetore (Model years 2001 ~ ????)
Main Jet - #162.5
Pilot Jet - #22.5
Float Height Settings - 14mm ~ 15mm
Idling Speed - 1200r/min ~ 1400r/min

I couldn't have found these settings without the help of "Madmax", an esteemed SR elder from the SR500forum. He deserves all the credits about me finding out above information.