Forum

[Beezabryan]

I am amazed that Hitchcock have supplied such a shite insert at £19.50 plus VAT and postage.............I wonder did they supply the correct seat? Perhaps a phone call is in order...... no need to go fitting a nonstandard valve, waste of money, the problem will still be there.

[simon]

I'd look at the mixture as valve seat regression is definitely made worse by the introduction of lead free petrol but a well tuned motor will still go fine. I recently looked at a completely original iron head off a 1950 G 80 Matchless and whilst there was reasonable about of wear there was no sign of seat regression. As the issue is happening on long runs I'd be tempted to go,for a larger main jet and see what colour the plug is with a test that involves killing the motor at speed so you can see the cylinder environment at full throttle.

[Mikey238]

Hi all ----- i've just finished taking the head off the engine. The exhaust valve has dug itself down into the seat about 4mm and created its own 'lip' in the seat where not more than 2000miles it stood slightly proud when it was brand new. This most recent issue has happened in what i reckon to be 250 miles... I hope these links work - the are to three close up pictures of the valve - as ever, thoughts are much appreciated!
https://dl.dropbox.com/u/100262052/IMG_6130.JPG
https://dl.dropbox.com/u/100262052/IMG_6125.JPG
https://dl.dropbox.com/u/100262052/IMG_6124.JPG

[Peter 53]

Mikey, I had a valve seat problem last year and was assisted by a very kind gentleman from this forum to get US manufactured valve seats fitted at a dedicated Head Shop in Warrington. This, in conjunction with the HM larger exhaust valve has completely sorted out the problem. Cost was about £200 all in as I remember it. My bike is a 1999 Bullet 500 made for Indian market, and I had done less than 1000 miles on it before it started playing up. I can send you my old exhaust valve if you need a quick fix until you can afford to get it done right? Contact me at chopper667 - at - gmail.com.

[Alan R]

Hi Guys--------- Am I glad that you have posted this problem. Not that I have any pleasure in your misfortune Mikey238 but because I also have recently removed a Hitchcocks O/S Ex. valve that had done just 3,250 miles before giving signs of failure...Upon removal it looked EXACTLY like yours, complete with all those little "flecks" attached to the seat area.....I returned it to our hosts for inspection---- their initial response was that the engine was running weak/hot etc... I pointed out that it was set to their recommended jetting figures and that the plug was quite normal.... They have sent it away to the manufacturers for their comments....This was approx 4 - 6 weeks ago...NOW, here is a common factor}---- That particular head is from an Indian home market bike which has done 12,732 Kms (about 7,500 miles) and the big valve was fitted as a direct replacement for the Indian original.. The exhaust seats that Hitchcocks supply ARE of European make but are NOT advertised as being hardened ie by implication they are therefor to ORIGINAL spec. ergo that's where the problem lies IMHO... I'm visiting the "Chaps at Chadwick" this Friday so will bring this post to their attention...Their larger exhaust valve (with extra slippery coating etc.) is advertised---as I understand it----- to be a direct replacement for the standard Ex. valve based on size alone.... There would appear, at this stage at least, to be a compatibility problem between the valve itself and the material the seat is made of...as PETER 53 says}--- he has a HARDENED seat, US made, with Hitchcocks larger valve and that combination is working OK....

[Freddy W]

2004 Bullet Sixty-5,… 8,000 miles………..
Hi Alan R and Mickey. I had this problem back in September. Search for blobs on this forum, I included Pics that looked exactly like yours.………. I showed this V/V to several bike mechanics and provoked much head scratching but no definitive reason. The closest explanation I got was from Rockhampton Henry who said perhaps Weak mixture or poor metal, but anyway after he fitted seats and V/V’s for me it’s been running fine for 700 miles. Alan, you could mention my “Blobs” as well when you go up to see the guys on Friday. This seems to be a common problem as Grunda also said he had the same blobs. I would dearly love to know a solid bit of reasoning as to how this Bullet feature happens. ……..Regards Blobby Fred

[Alan R]

Hi guys------- FREDDY & Co.--- will send an E-Mail to our hosts directing their attention to this thread before Friday so that they can have time to have a look etc.

[Phil Ashbrook]

My 1995 500 export manual was wrong to say unleaded fuel was OK , I had the same problem until I got the oversize exhaust valve and started using valve saver fluid but you can get bottles of lead booster from race car teams , the seats are too soft on standard heads , if I get valve seat recession again with the bigger hence cooler running exhaust valve it's a valve seat replacement or I could get the Fury head wich runs cooler and will last longer in everyway , my intended switch to E85 fuel will help as well .

[Alan R]

Hi guys !! ---------------- good news !! ie Christmas/New Year is over and done with (That's my "Scrooge au natural" coming out there).... Well, I had a chat with our hosts re}--My damaged o/s valve which-- if you remember ---they had returned to the manufacturer for their comments ??....We had a short chat, I mentioned that others have had similar problems and I broached the possibility that the Hitchcocks replacement, European-made valve seat might be to the same spec as the original Indian-made item, thus giving the problems ?? (This idea was based on the fact that the catalogue listing doesn't actually state the seats to be hardened or harder ).. Our hosts were quite adamant that their replacement seats ARE harder/hardened compared to original equipment as fitted...With regards to my O/S valve}--- they had a preliminary report back but, as I understand it, were awaiting a fuller, printed report which along with the valve---is to be returned to me ASAP after the Hols..When that arrives I'll let you know....Meanwhile>>>>>> where's the photos ????

[Alan R]

------------ sorry, have just found the links ---- ignore that last question