Speed 400 Top End Disaster

Tosgha · Sep 12, 2025 at 6:44 PM

Last thursday the 400 started to get really noisey in the top end on the way to work, very clattery. WhenI went to go home it would not start up, only the starter motor turning over. RAC took to dealers and the diagnoses is the top end is toast. Cam, valves and pretty much everything else will need replacing. Good news is it will be a warranty job as the bike is only 15 months old and about 1500 miles. Best guess is the cam chain tensioner failed and the chain jumped a tooth. Any one else hear about similar issues?

TRIPLE X · Sep 12, 2025 at 6:53 PM

Tosgha said: ↑

Last thursday the 400 started to get really noisey in the top end on the way to work, very clattery. WhenI went to go home it would not start up, only the starter motor turning over. RAC took to dealers and the diagnoses is the top end is toast. Cam, valves and pretty much everything else will need replacing. Good news is it will be a warranty job as the bike is only 15 months old and about 1500 miles. Best guess is the cam chain tensioner failed and the chain jumped a tooth. Any one else hear about similar issues?
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Do keep us informed. Interested to know what went wrong.

ajc400 · Sep 12, 2025 at 7:58 PM

Yep, I read a few reports of engine troubles (have a look on the Triumph400 forum, I was/still am a member) - cam chain tensioner can "fail" and chain can wear the casings. Check oil filters for swarf. Also some which needed valve clearances adjusted.

Frustratingly, some bikes are fine, it's a slight lottery..... My engine was a bit metallic sounding at times (3000 miles) - I had a slight bump and sold it through the insurance claims agent as I decided I didn't want it back.

I was a bit disappointed with the Triumph for a few niggly faults and noises, and went back to Honda. I lost quite a few £££.