Mid 2023 I had my engine completely out and I re-set the balance factor along with a few other little jobs. Added a extra breather in to the push rod tunnel up to the rocker box and replaced the lifters.
I've been reading and researching this for well over a year now! Going back as far as technical motorcycle books from the 1960s and articles from 30 years ago. It's a bit of a dark art. Finally got enough confidence to have a go myself.
Crank out on my "V" bearing jig. Double checked the run-out on the jig and between centers on my lathe. What I've found with 2 RE cranks I've worked on (so far) that the machined centers cannot be trusted on the shafts.
On the jig, The crank had 0 run out on the bearing landings and 0.01 to 0.02mm at the shaft ends. Not worth trying to improve on.
So far I've re-set the Balance Factor my 535 Iron Barrel/AVL Head hybrid 8.5kg crankshaft and assembled the bottom end and now my GT535.
Modified my jig so knife edges can be used for checking the hanging weight on the small end.
My GT535 UCE crank is a 8.3kg crank. Pretty well the same as a Classic 350 crank which is pictured on the knife edges, visible is the different balancing holes. Where as the Classic UCE 500 is a 10.5kg crank.
In stock form with the stock cast 87mm piston the Balance factor for the GT535 is 57%. With the Hitchcocks 87mm +10 forged piston was 58% due to the forged piston is 10 grams heavier than the stock cast piston.
I raised the Balance factor to 63% which seemed to common consensus answers I got suitable for the GT535 the crankshaft assembly needed to be altered by 30 grams. Which was done by strategic drilling on the light side.
Now on to the verdict. I've been riding it for 3 weeks now so I can ride it in all different conditions with the re-balanced crank assembly.
Vibration, What it didn't do was eliminate it, but it was a very big improvement. Worth the cost of a gasket kit and a weekend of tinkering.
As easy visual control for me was the levers, easy enough see and how bloody annoying it was. Around 3000rpm to 3400rpm (80-90km/h) the levers used to flap and buzz like crazy, previously I'd always had to rest 2 fingers on them to prevent this. Now around those rpms speeds it's super smooth, Probably the smoothest.
100km/hr is a little better than before. But where it shines the most is it will happily rev smoothly all the way to redline. Before it would make the speedo a blur and felt like it was going to shake itself to bits from 4500rpm to redline.
I've seen it's a common issue with GT535s and rode 2 other stock ones for comparison which were the same. They break speedo/tacho clocks by rattling their insides and also snapping the speedo mounts, one of which had a broken speedo bracket, the other on its 2nd set of clocks.
I'm quite happy with the outcome. And have a UCE Classic 500 shortly to change it's balance factor also. I've learned a lot why the crankshaft weights have changed over the years!
My area in Australia the common complaint about the UCE Classic 500 is vibration and how slow they are. But I think they are ridden slow due to the vibration. So I'll see if I can improve on my friends bike as a test.
The next little modification was making the breathing system a little better. Inspiration from what Bullet Whisperer does to his Bullet builds along from the "Bunn Breather" systems. I'll be doing the "Top Down" style. Since the oil pump sends near 4 litres a minute around the engine oil will want to be forced out of the upper breather. So a one way valve needs to be installed.
Arrows are non return valves and blue is a filter. It could be plumbed back into the airbox. But I decided it looked neater without hoses going everywhere.
Found a suitable spot in the RH side case casting above the Lifter keeper bracket. A circular blob in the casting, drilled a 3mm hole, tapped a thread incase if its a failure and I need to bung it up.
Even makes me wonder if it was there for a single stud for a tappet cover like the Iron Barrels.
I found that the engine could of had breathing issues, despite having a open type breather on the breather fitting on the RHS case. First was brand new kick starter seals leaking. Replaced them, then other leaks and issues with o-ring seals despite my efforts. 3 weeks of riding with the new breather system in and no leaks at all now.
Here's the plumbing so far to make sure it's all working as intended. A non return valve is drilled and tapped into the Exhaust Rocker box to the right for clearance. Spun up on the lathe a little fitting bracket to mount the breather pod filter.
Also using the RHS case breather chamber as intended. Which works like a little internal catch can trapping any oil mist and sending in back to the sump whilst letting cooled crank case gases out to atmosphere. No mess on the floor yet either. So far so good!
While I was at it I replaced the lifters. A common trend I see with Indian RE bearings is the case hardening of their bearings and races aren't really up to par with European/Japanese made bearings. Hear you can see the roller of the lifter with a bit of de-lamination. I think there's a American lifter that can be purchased that is a common item in their V8s? But I ended up installing standard ones again. They lasted 30,000kms without failure, just delamination.
Did I need to do all these things? Probably not. But this is a hobby, I do 99% everything myself and enjoy learning and taking notes from those who are in the know along the way. Then getting to test and ride my efforts.
Most of all, proud of my work.
Have a great weekend chaps.
Topic: A "Rockers" GT535 (Read 6884 times)