Hitchcocks Forum

Hi everyone....I just acquired a 1991 350 Bullet. I wanted to know if unleaded petrol would be OK re valve seat recession, or is it essential to use some kind of additive?

jez, Indian Bullets of this period have a reputation for poor metallurgy so I think I'd use an additive anyway!
REgards, Mark

--------- sorry to be a "Harbinger of DOOM" but a (limited) choice of fuel is only going to delay the inevitable IF your head hasn't been off at all...My honest advice would be that you have TWO choices viz 1).. Obtain a spare head and build it up to modern specs and then do a swap-over ( Thus keeping your bike on the road for as long as possible) OR ..2) Have your head re-worked asap............................. You'll know when it happens as the exhaust tappet tightens up and you loose all compression..If it does this whilst out and about, don't worry--just re-set the tappet to the zero setting again and off you go BUT---once it has happened that's the warning sign for the upgrading to be done......TIP}--- In the inspection plate at the base of the barell, remove the threaded stud and replace with a bolt. Now you can use ordinary spanners on those adjuster nuts !!!................................. My "Recession" happened at the Stafford show a few years back... Just got kitted-up to come home and NO COMPRESSION !!... A coach-load of "Gentlemen from Wales" gave me much-needed "Verbal Assistance"-----and after re-setting the tappets it started second kick ( Thank God !!)-------

Stock seats are very soft , my 1995 500 has a larger exhaust valve but it wont be long before I need a new seat , I'm just lucky my seat has not worked loose.

Have had a 95 350 from new and run on unleaded/no addatives from day one, now done over 21000km,if it ain't broke don't fix it. You could use addative for peace of mind if your that way inclined,any idea if it has had addatives in the past.

Gentlemen it must be an Indian or mettalurgical problem. My 50's Ariel and Norton, my 60's Norton and BSA and finally my 70's Commando all run perfectly on unleaded without any modification and without any problems. As I have often said before my 1958 Model 50 has actually done 83000 miles without the engine being stripped and without the head coming off. If I can remember how to do this here it is



And here is the Commando


As you can see nothing wrong with the valve seats on these two.

----------NICE !!!!!... A few years back I had the chance of a lovely "oily rag" 1950's ES2 --- went back for a second look and it had gone !! Much Anglo-Saxon words and Boo-Hooing in the car going home !! ( Joyce looked at me quizzically )..... you understand, don't you ??

------------- sorry JEZZA, gone "Off Piste" a bit there..

Thanks everyone for all the responses. Yes it has been run with additives before, so I will continue doing so. In essence it appears that there is no difinitive answer - bit of a case of suck it and see. It seems very much pot luck as to what extent seat recession will affect any one particular engine. One day, when I'm feeling a bit more adventurous, I will pull the head off and take a gander at the valves and seats to see what is going on. No such trouble with my Turbo Twin - good old two strokes eh?

Yes, that's the best approach I think.. At least you now know what MIGHT happen, and how it will show itself...It's an "old chestnut" with loads of experiences/engineering contacts etc on here should you need it..... Get yer leg over the saddle and enjoy what's left of this weather.......... Ride Safe !!